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FFmpeg/libavcodec/mjpeg.c

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  1. /*

  2.  * MJPEG encoder and decoder

  3.  * Copyright (c) 2000, 2001 Fabrice Bellard.

  4.  *

  5.  * This library is free software; you can redistribute it and/or

  6.  * modify it under the terms of the GNU Lesser General Public

  7.  * License as published by the Free Software Foundation; either

  8.  * version 2 of the License, or (at your option) any later version.

  9.  *

  10.  * This library is distributed in the hope that it will be useful,

  11.  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  12.  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

  13.  * Lesser General Public License for more details.

  14.  *

  15.  * You should have received a copy of the GNU Lesser General Public

  16.  * License along with this library; if not, write to the Free Software

  17.  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

  18.  *

  19.  * Support for external huffman table, various fixes (AVID workaround),

  20.  * aspecting, new decode_frame mechanism and apple mjpeg-b support

  21.  *                                  by Alex Beregszaszi <alex@naxine.org>

  22.  */

  23. 

  24. /**

  25.  * @file mjpeg.c

  26.  * MJPEG encoder and decoder.

  27.  */

  28.  

  29. //#define DEBUG

  30. #include "avcodec.h"

  31. #include "dsputil.h"

  32. #include "mpegvideo.h"

  33. 

  34. /* use two quantizer tables (one for luminance and one for chrominance) */

  35. /* not yet working */

  36. #undef TWOMATRIXES

  37. 

  38. typedef struct MJpegContext {

  39.     uint8_t huff_size_dc_luminance[12];

  40.     uint16_t huff_code_dc_luminance[12];

  41.     uint8_t huff_size_dc_chrominance[12];

  42.     uint16_t huff_code_dc_chrominance[12];

  43. 

  44.     uint8_t huff_size_ac_luminance[256];

  45.     uint16_t huff_code_ac_luminance[256];

  46.     uint8_t huff_size_ac_chrominance[256];

  47.     uint16_t huff_code_ac_chrominance[256];

  48. } MJpegContext;

  49. 

  50. /* JPEG marker codes */

  51. typedef enum {

  52.     /* start of frame */

  53.     SOF0  = 0xc0,	/* baseline */

  54.     SOF1  = 0xc1,	/* extended sequential, huffman */

  55.     SOF2  = 0xc2,	/* progressive, huffman */

  56.     SOF3  = 0xc3,	/* lossless, huffman */

  57. 

  58.     SOF5  = 0xc5,	/* differential sequential, huffman */

  59.     SOF6  = 0xc6,	/* differential progressive, huffman */

  60.     SOF7  = 0xc7,	/* differential lossless, huffman */

  61.     JPG   = 0xc8,	/* reserved for JPEG extension */

  62.     SOF9  = 0xc9,	/* extended sequential, arithmetic */

  63.     SOF10 = 0xca,	/* progressive, arithmetic */

  64.     SOF11 = 0xcb,	/* lossless, arithmetic */

  65. 

  66.     SOF13 = 0xcd,	/* differential sequential, arithmetic */

  67.     SOF14 = 0xce,	/* differential progressive, arithmetic */

  68.     SOF15 = 0xcf,	/* differential lossless, arithmetic */

  69. 

  70.     DHT   = 0xc4,	/* define huffman tables */

  71. 

  72.     DAC   = 0xcc,	/* define arithmetic-coding conditioning */

  73. 

  74.     /* restart with modulo 8 count "m" */

  75.     RST0  = 0xd0,

  76.     RST1  = 0xd1,

  77.     RST2  = 0xd2,

  78.     RST3  = 0xd3,

  79.     RST4  = 0xd4,

  80.     RST5  = 0xd5,

  81.     RST6  = 0xd6,

  82.     RST7  = 0xd7,

  83. 

  84.     SOI   = 0xd8,	/* start of image */

  85.     EOI   = 0xd9,	/* end of image */

  86.     SOS   = 0xda,	/* start of scan */

  87.     DQT   = 0xdb,	/* define quantization tables */

  88.     DNL   = 0xdc,	/* define number of lines */

  89.     DRI   = 0xdd,	/* define restart interval */

  90.     DHP   = 0xde,	/* define hierarchical progression */

  91.     EXP   = 0xdf,	/* expand reference components */

  92. 

  93.     APP0  = 0xe0,

  94.     APP1  = 0xe1,

  95.     APP2  = 0xe2,

  96.     APP3  = 0xe3,

  97.     APP4  = 0xe4,

  98.     APP5  = 0xe5,

  99.     APP6  = 0xe6,

  100.     APP7  = 0xe7,

  101.     APP8  = 0xe8,

  102.     APP9  = 0xe9,

  103.     APP10 = 0xea,

  104.     APP11 = 0xeb,

  105.     APP12 = 0xec,

  106.     APP13 = 0xed,

  107.     APP14 = 0xee,

  108.     APP15 = 0xef,

  109. 

  110.     JPG0  = 0xf0,

  111.     JPG1  = 0xf1,

  112.     JPG2  = 0xf2,

  113.     JPG3  = 0xf3,

  114.     JPG4  = 0xf4,

  115.     JPG5  = 0xf5,

  116.     JPG6  = 0xf6,

  117.     JPG7  = 0xf7,

  118.     JPG8  = 0xf8,

  119.     JPG9  = 0xf9,

  120.     JPG10 = 0xfa,

  121.     JPG11 = 0xfb,

  122.     JPG12 = 0xfc,

  123.     JPG13 = 0xfd,

  124. 

  125.     COM   = 0xfe,	/* comment */

  126. 

  127.     TEM   = 0x01,	/* temporary private use for arithmetic coding */

  128. 

  129.     /* 0x02 -> 0xbf reserved */

  130. } JPEG_MARKER;

  131. 

  132. #if 0

  133. /* These are the sample quantization tables given in JPEG spec section K.1.

  134.  * The spec says that the values given produce "good" quality, and

  135.  * when divided by 2, "very good" quality.

  136.  */

  137. static const unsigned char std_luminance_quant_tbl[64] = {

  138.     16,  11,  10,  16,  24,  40,  51,  61,

  139.     12,  12,  14,  19,  26,  58,  60,  55,

  140.     14,  13,  16,  24,  40,  57,  69,  56,

  141.     14,  17,  22,  29,  51,  87,  80,  62,

  142.     18,  22,  37,  56,  68, 109, 103,  77,

  143.     24,  35,  55,  64,  81, 104, 113,  92,

  144.     49,  64,  78,  87, 103, 121, 120, 101,

  145.     72,  92,  95,  98, 112, 100, 103,  99

  146. };

  147. static const unsigned char std_chrominance_quant_tbl[64] = {

  148.     17,  18,  24,  47,  99,  99,  99,  99,

  149.     18,  21,  26,  66,  99,  99,  99,  99,

  150.     24,  26,  56,  99,  99,  99,  99,  99,

  151.     47,  66,  99,  99,  99,  99,  99,  99,

  152.     99,  99,  99,  99,  99,  99,  99,  99,

  153.     99,  99,  99,  99,  99,  99,  99,  99,

  154.     99,  99,  99,  99,  99,  99,  99,  99,

  155.     99,  99,  99,  99,  99,  99,  99,  99

  156. };

  157. #endif

  158. 

  159. /* Set up the standard Huffman tables (cf. JPEG standard section K.3) */

  160. /* IMPORTANT: these are only valid for 8-bit data precision! */

  161. static const uint8_t bits_dc_luminance[17] =

  162. { /* 0-base */ 0, 0, 1, 5, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0 };

  163. static const uint8_t val_dc_luminance[] =

  164. { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  165. 

  166. static const uint8_t bits_dc_chrominance[17] =

  167. { /* 0-base */ 0, 0, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0 };

  168. static const uint8_t val_dc_chrominance[] =

  169. { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 };

  170. 

  171. static const uint8_t bits_ac_luminance[17] =

  172. { /* 0-base */ 0, 0, 2, 1, 3, 3, 2, 4, 3, 5, 5, 4, 4, 0, 0, 1, 0x7d };

  173. static const uint8_t val_ac_luminance[] =

  174. { 0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12,

  175.   0x21, 0x31, 0x41, 0x06, 0x13, 0x51, 0x61, 0x07,

  176.   0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08,

  177.   0x23, 0x42, 0xb1, 0xc1, 0x15, 0x52, 0xd1, 0xf0,

  178.   0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16,

  179.   0x17, 0x18, 0x19, 0x1a, 0x25, 0x26, 0x27, 0x28,

  180.   0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39,

  181.   0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49,

  182.   0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59,

  183.   0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69,

  184.   0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79,

  185.   0x7a, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89,

  186.   0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98,

  187.   0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,

  188.   0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6,

  189.   0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3, 0xc4, 0xc5,

  190.   0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4,

  191.   0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xe1, 0xe2,

  192.   0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea,

  193.   0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

  194.   0xf9, 0xfa 

  195. };

  196. 

  197. static const uint8_t bits_ac_chrominance[17] =

  198. { /* 0-base */ 0, 0, 2, 1, 2, 4, 4, 3, 4, 7, 5, 4, 4, 0, 1, 2, 0x77 };

  199. 

  200. static const uint8_t val_ac_chrominance[] =

  201. { 0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21,

  202.   0x31, 0x06, 0x12, 0x41, 0x51, 0x07, 0x61, 0x71,

  203.   0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91,

  204.   0xa1, 0xb1, 0xc1, 0x09, 0x23, 0x33, 0x52, 0xf0,

  205.   0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34,

  206.   0xe1, 0x25, 0xf1, 0x17, 0x18, 0x19, 0x1a, 0x26,

  207.   0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38,

  208.   0x39, 0x3a, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48,

  209.   0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58,

  210.   0x59, 0x5a, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68,

  211.   0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78,

  212.   0x79, 0x7a, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,

  213.   0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96,

  214.   0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3, 0xa4, 0xa5,

  215.   0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4,

  216.   0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xc2, 0xc3,

  217.   0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2,

  218.   0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda,

  219.   0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9,

  220.   0xea, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8,

  221.   0xf9, 0xfa 

  222. };

  223. 

  224. /* isn't this function nicer than the one in the libjpeg ? */

  225. static void build_huffman_codes(uint8_t *huff_size, uint16_t *huff_code,

  226.                                 const uint8_t *bits_table, const uint8_t *val_table)

  227. {

  228.     int i, j, k,nb, code, sym;

  229. 

  230.     code = 0;

  231.     k = 0;

  232.     for(i=1;i<=16;i++) {

  233.         nb = bits_table[i];

  234.         for(j=0;j<nb;j++) {

  235.             sym = val_table[k++];

  236.             huff_size[sym] = i;

  237.             huff_code[sym] = code;

  238.             code++;

  239.         }

  240.         code <<= 1;

  241.     }

  242. }

  243. 

  244. int mjpeg_init(MpegEncContext *s)

  245. {

  246.     MJpegContext *m;

  247.     

  248.     m = av_malloc(sizeof(MJpegContext));

  249.     if (!m)

  250.         return -1;

  251.     

  252.     s->min_qcoeff=-1023;

  253.     s->max_qcoeff= 1023;

  254.     s->intra_quant_bias= 1<<(QUANT_BIAS_SHIFT-1); //(a + x/2)/x

  255. 

  256.     /* build all the huffman tables */

  257.     build_huffman_codes(m->huff_size_dc_luminance,

  258.                         m->huff_code_dc_luminance,

  259.                         bits_dc_luminance,

  260.                         val_dc_luminance);

  261.     build_huffman_codes(m->huff_size_dc_chrominance,

  262.                         m->huff_code_dc_chrominance,

  263.                         bits_dc_chrominance,

  264.                         val_dc_chrominance);

  265.     build_huffman_codes(m->huff_size_ac_luminance,

  266.                         m->huff_code_ac_luminance,

  267.                         bits_ac_luminance,

  268.                         val_ac_luminance);

  269.     build_huffman_codes(m->huff_size_ac_chrominance,

  270.                         m->huff_code_ac_chrominance,

  271.                         bits_ac_chrominance,

  272.                         val_ac_chrominance);

  273.     

  274.     s->mjpeg_ctx = m;

  275.     return 0;

  276. }

  277. 

  278. void mjpeg_close(MpegEncContext *s)

  279. {

  280.     av_free(s->mjpeg_ctx);

  281. }

  282. 

  283. static inline void put_marker(PutBitContext *p, int code)

  284. {

  285.     put_bits(p, 8, 0xff);

  286.     put_bits(p, 8, code);

  287. }

  288. 

  289. /* table_class: 0 = DC coef, 1 = AC coefs */

  290. static int put_huffman_table(MpegEncContext *s, int table_class, int table_id,

  291.                              const uint8_t *bits_table, const uint8_t *value_table)

  292. {

  293.     PutBitContext *p = &s->pb;

  294.     int n, i;

  295. 

  296.     put_bits(p, 4, table_class);

  297.     put_bits(p, 4, table_id);

  298. 

  299.     n = 0;

  300.     for(i=1;i<=16;i++) {

  301.         n += bits_table[i];

  302.         put_bits(p, 8, bits_table[i]);

  303.     }

  304. 

  305.     for(i=0;i<n;i++)

  306.         put_bits(p, 8, value_table[i]);

  307. 

  308.     return n + 17;

  309. }

  310. 

  311. static void jpeg_table_header(MpegEncContext *s)

  312. {

  313.     PutBitContext *p = &s->pb;

  314.     int i, j, size;

  315.     uint8_t *ptr;

  316. 

  317.     /* quant matrixes */

  318.     put_marker(p, DQT);

  319. #ifdef TWOMATRIXES

  320.     put_bits(p, 16, 2 + 2 * (1 + 64));

  321. #else

  322.     put_bits(p, 16, 2 + 1 * (1 + 64));

  323. #endif

  324.     put_bits(p, 4, 0); /* 8 bit precision */

  325.     put_bits(p, 4, 0); /* table 0 */

  326.     for(i=0;i<64;i++) {

  327.         j = s->intra_scantable.permutated[i];

  328.         put_bits(p, 8, s->intra_matrix[j]);

  329.     }

  330. #ifdef TWOMATRIXES

  331.     put_bits(p, 4, 0); /* 8 bit precision */

  332.     put_bits(p, 4, 1); /* table 1 */

  333.     for(i=0;i<64;i++) {

  334.         j = s->intra_scantable.permutated[i];

  335.         put_bits(p, 8, s->chroma_intra_matrix[j]);

  336.     }

  337. #endif

  338. 

  339.     /* huffman table */

  340.     put_marker(p, DHT);

  341.     flush_put_bits(p);

  342.     ptr = pbBufPtr(p);

  343.     put_bits(p, 16, 0); /* patched later */

  344.     size = 2;

  345.     size += put_huffman_table(s, 0, 0, bits_dc_luminance, val_dc_luminance);

  346.     size += put_huffman_table(s, 0, 1, bits_dc_chrominance, val_dc_chrominance);

  347.     

  348.     size += put_huffman_table(s, 1, 0, bits_ac_luminance, val_ac_luminance);

  349.     size += put_huffman_table(s, 1, 1, bits_ac_chrominance, val_ac_chrominance);

  350.     ptr[0] = size >> 8;

  351.     ptr[1] = size;

  352. }

  353. 

  354. static void jpeg_put_comments(MpegEncContext *s)

  355. {

  356.     PutBitContext *p = &s->pb;

  357.     int size;

  358.     uint8_t *ptr;

  359. 

  360.     if (s->aspect_ratio_info)

  361.     {

  362.     /* JFIF header */

  363.     put_marker(p, APP0);

  364.     put_bits(p, 16, 16);

  365.     put_string(p, "JFIF"); /* this puts the trailing zero-byte too */

  366.     put_bits(p, 16, 0x0201); /* v 1.02 */

  367.     put_bits(p, 8, 0); /* units type: 0 - aspect ratio */

  368.     switch(s->aspect_ratio_info)

  369.     {

  370. 	case FF_ASPECT_4_3_625:

  371. 	case FF_ASPECT_4_3_525:

  372. 	    put_bits(p, 16, 4); 

  373. 	    put_bits(p, 16, 3);

  374. 	    break;

  375. 	case FF_ASPECT_16_9_625:

  376. 	case FF_ASPECT_16_9_525:

  377. 	    put_bits(p, 16, 16); 

  378. 	    put_bits(p, 16, 9);

  379. 	    break;

  380. 	case FF_ASPECT_EXTENDED:

  381. 	    put_bits(p, 16, s->aspected_width);

  382. 	    put_bits(p, 16, s->aspected_height);

  383. 	    break;

  384. 	case FF_ASPECT_SQUARE:

  385. 	default:

  386. 	    put_bits(p, 16, 1); /* aspect: 1:1 */

  387. 	    put_bits(p, 16, 1);

  388. 	    break;

  389.     }

  390.     put_bits(p, 8, 0); /* thumbnail width */

  391.     put_bits(p, 8, 0); /* thumbnail height */

  392.     }

  393. 

  394.     /* comment */

  395.     if(!(s->flags & CODEC_FLAG_BITEXACT)){

  396.         put_marker(p, COM);

  397.         flush_put_bits(p);

  398.         ptr = pbBufPtr(p);

  399.         put_bits(p, 16, 0); /* patched later */

  400.         put_string(p, LIBAVCODEC_IDENT);

  401.         size = strlen(LIBAVCODEC_IDENT)+3;

  402.         ptr[0] = size >> 8;

  403.         ptr[1] = size;

  404.     }

  405. }

  406. 

  407. void mjpeg_picture_header(MpegEncContext *s)

  408. {

  409.     put_marker(&s->pb, SOI);

  410. 

  411.     if (!s->mjpeg_data_only_frames)

  412.     {

  413.     jpeg_put_comments(s);    

  414. 

  415.     if (s->mjpeg_write_tables) jpeg_table_header(s);

  416. 

  417.     put_marker(&s->pb, SOF0);

  418. 

  419.     put_bits(&s->pb, 16, 17);

  420.     put_bits(&s->pb, 8, 8); /* 8 bits/component */

  421.     put_bits(&s->pb, 16, s->height);

  422.     put_bits(&s->pb, 16, s->width);

  423.     put_bits(&s->pb, 8, 3); /* 3 components */

  424.     

  425.     /* Y component */

  426.     put_bits(&s->pb, 8, 1); /* component number */

  427.     put_bits(&s->pb, 4, s->mjpeg_hsample[0]); /* H factor */

  428.     put_bits(&s->pb, 4, s->mjpeg_vsample[0]); /* V factor */

  429.     put_bits(&s->pb, 8, 0); /* select matrix */

  430.     

  431.     /* Cb component */

  432.     put_bits(&s->pb, 8, 2); /* component number */

  433.     put_bits(&s->pb, 4, s->mjpeg_hsample[1]); /* H factor */

  434.     put_bits(&s->pb, 4, s->mjpeg_vsample[1]); /* V factor */

  435. #ifdef TWOMATRIXES

  436.     put_bits(&s->pb, 8, 1); /* select matrix */

  437. #else

  438.     put_bits(&s->pb, 8, 0); /* select matrix */

  439. #endif

  440. 

  441.     /* Cr component */

  442.     put_bits(&s->pb, 8, 3); /* component number */

  443.     put_bits(&s->pb, 4, s->mjpeg_hsample[2]); /* H factor */

  444.     put_bits(&s->pb, 4, s->mjpeg_vsample[2]); /* V factor */

  445. #ifdef TWOMATRIXES

  446.     put_bits(&s->pb, 8, 1); /* select matrix */

  447. #else

  448.     put_bits(&s->pb, 8, 0); /* select matrix */

  449. #endif

  450.     }

  451. 

  452.     /* scan header */

  453.     put_marker(&s->pb, SOS);

  454.     put_bits(&s->pb, 16, 12); /* length */

  455.     put_bits(&s->pb, 8, 3); /* 3 components */

  456.     

  457.     /* Y component */

  458.     put_bits(&s->pb, 8, 1); /* index */

  459.     put_bits(&s->pb, 4, 0); /* DC huffman table index */

  460.     put_bits(&s->pb, 4, 0); /* AC huffman table index */

  461.     

  462.     /* Cb component */

  463.     put_bits(&s->pb, 8, 2); /* index */

  464.     put_bits(&s->pb, 4, 1); /* DC huffman table index */

  465.     put_bits(&s->pb, 4, 1); /* AC huffman table index */

  466.     

  467.     /* Cr component */

  468.     put_bits(&s->pb, 8, 3); /* index */

  469.     put_bits(&s->pb, 4, 1); /* DC huffman table index */

  470.     put_bits(&s->pb, 4, 1); /* AC huffman table index */

  471. 

  472.     put_bits(&s->pb, 8, 0); /* Ss (not used) */

  473.     put_bits(&s->pb, 8, 63); /* Se (not used) */

  474.     put_bits(&s->pb, 8, 0); /* Ah/Al (not used) */

  475. }

  476. 

  477. static void escape_FF(MpegEncContext *s, int start)

  478. {

  479.     int size= get_bit_count(&s->pb) - start*8;

  480.     int i, ff_count;

  481.     uint8_t *buf= s->pb.buf + start;

  482.     int align= (-(int)(buf))&3;

  483.     

  484.     assert((size&7) == 0);

  485.     size >>= 3;

  486.     

  487.     ff_count=0;

  488.     for(i=0; i<size && i<align; i++){

  489.         if(buf[i]==0xFF) ff_count++;

  490.     }

  491.     for(; i<size-15; i+=16){

  492.         int acc, v;

  493. 

  494.         v= *(uint32_t*)(&buf[i]);

  495.         acc= (((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;

  496.         v= *(uint32_t*)(&buf[i+4]);

  497.         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;

  498.         v= *(uint32_t*)(&buf[i+8]);

  499.         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;

  500.         v= *(uint32_t*)(&buf[i+12]);

  501.         acc+=(((v & (v>>4))&0x0F0F0F0F)+0x01010101)&0x10101010;

  502. 

  503.         acc>>=4;

  504.         acc+= (acc>>16);

  505.         acc+= (acc>>8);

  506.         ff_count+= acc&0xFF;

  507.     }

  508.     for(; i<size; i++){

  509.         if(buf[i]==0xFF) ff_count++;

  510.     }

  511. 

  512.     if(ff_count==0) return;

  513.     

  514.     /* skip put bits */

  515.     for(i=0; i<ff_count-3; i+=4)

  516.         put_bits(&s->pb, 32, 0);

  517.     put_bits(&s->pb, (ff_count-i)*8, 0);

  518.     flush_put_bits(&s->pb); 

  519. 

  520.     for(i=size-1; ff_count; i--){

  521.         int v= buf[i];

  522. 

  523.         if(v==0xFF){

  524. //printf("%d %d\n", i, ff_count);

  525.             buf[i+ff_count]= 0;

  526.             ff_count--;

  527.         }

  528. 

  529.         buf[i+ff_count]= v;

  530.     }

  531. }

  532. 

  533. void mjpeg_picture_trailer(MpegEncContext *s)

  534. {

  535.     int pad= (-get_bit_count(&s->pb))&7;

  536.     

  537.     put_bits(&s->pb, pad,0xFF>>(8-pad));

  538.     flush_put_bits(&s->pb);

  539. 

  540.     assert((s->header_bits&7)==0);

  541.     

  542.     escape_FF(s, s->header_bits>>3);

  543. 

  544.     put_marker(&s->pb, EOI);

  545. }

  546. 

  547. static inline void mjpeg_encode_dc(MpegEncContext *s, int val,

  548. 				   uint8_t *huff_size, uint16_t *huff_code)

  549. {

  550.     int mant, nbits;

  551. 

  552.     if (val == 0) {

  553.         put_bits(&s->pb, huff_size[0], huff_code[0]);

  554.     } else {

  555.         mant = val;

  556.         if (val < 0) {

  557.             val = -val;

  558.             mant--;

  559.         }

  560.         

  561.         /* compute the log (XXX: optimize) */

  562.         nbits = 0;

  563.         while (val != 0) {

  564.             val = val >> 1;

  565.             nbits++;

  566.         }

  567.             

  568.         put_bits(&s->pb, huff_size[nbits], huff_code[nbits]);

  569.         

  570.         put_bits(&s->pb, nbits, mant & ((1 << nbits) - 1));

  571.     }

  572. }

  573. 

  574. static void encode_block(MpegEncContext *s, DCTELEM *block, int n)

  575. {

  576.     int mant, nbits, code, i, j;

  577.     int component, dc, run, last_index, val;

  578.     MJpegContext *m = s->mjpeg_ctx;

  579.     uint8_t *huff_size_ac;

  580.     uint16_t *huff_code_ac;

  581.     

  582.     /* DC coef */

  583.     component = (n <= 3 ? 0 : n - 4 + 1);

  584.     dc = block[0]; /* overflow is impossible */

  585.     val = dc - s->last_dc[component];

  586.     if (n < 4) {

  587.         mjpeg_encode_dc(s, val, m->huff_size_dc_luminance, m->huff_code_dc_luminance);

  588.         huff_size_ac = m->huff_size_ac_luminance;

  589.         huff_code_ac = m->huff_code_ac_luminance;

  590.     } else {

  591.         mjpeg_encode_dc(s, val, m->huff_size_dc_chrominance, m->huff_code_dc_chrominance);

  592.         huff_size_ac = m->huff_size_ac_chrominance;

  593.         huff_code_ac = m->huff_code_ac_chrominance;

  594.     }

  595.     s->last_dc[component] = dc;

  596.     

  597.     /* AC coefs */

  598.     

  599.     run = 0;

  600.     last_index = s->block_last_index[n];

  601.     for(i=1;i<=last_index;i++) {

  602.         j = s->intra_scantable.permutated[i];

  603.         val = block[j];

  604.         if (val == 0) {

  605.             run++;

  606.         } else {

  607.             while (run >= 16) {

  608.                 put_bits(&s->pb, huff_size_ac[0xf0], huff_code_ac[0xf0]);

  609.                 run -= 16;

  610.             }

  611.             mant = val;

  612.             if (val < 0) {

  613.                 val = -val;

  614.                 mant--;

  615.             }

  616.             

  617.             /* compute the log (XXX: optimize) */

  618.             nbits = 0;

  619.             while (val != 0) {

  620.                 val = val >> 1;

  621.                 nbits++;

  622.             }

  623.             code = (run << 4) | nbits;

  624. 

  625.             put_bits(&s->pb, huff_size_ac[code], huff_code_ac[code]);

  626.         

  627.             put_bits(&s->pb, nbits, mant & ((1 << nbits) - 1));

  628.             run = 0;

  629.         }

  630.     }

  631. 

  632.     /* output EOB only if not already 64 values */

  633.     if (last_index < 63 || run != 0)

  634.         put_bits(&s->pb, huff_size_ac[0], huff_code_ac[0]);

  635. }

  636. 

  637. void mjpeg_encode_mb(MpegEncContext *s, 

  638.                      DCTELEM block[6][64])

  639. {

  640.     int i;

  641.     for(i=0;i<6;i++) {

  642.         encode_block(s, block[i], i);

  643.     }

  644. }

  645. 

  646. /******************************************/

  647. /* decoding */

  648. 

  649. #define MAX_COMPONENTS 4

  650. 

  651. typedef struct MJpegDecodeContext {

  652.     AVCodecContext *avctx;

  653.     GetBitContext gb;

  654.     int mpeg_enc_ctx_allocated; /* true if decoding context allocated */

  655. 

  656.     int start_code; /* current start code */

  657.     int buffer_size;

  658.     uint8_t *buffer;

  659. 

  660.     int16_t quant_matrixes[4][64];

  661.     VLC vlcs[2][4];

  662. 

  663.     int org_width, org_height;  /* size given at codec init */

  664.     int first_picture;    /* true if decoding first picture */

  665.     int interlaced;     /* true if interlaced */

  666.     int bottom_field;   /* true if bottom field */

  667. 

  668.     int width, height;

  669.     int nb_components;

  670.     int component_id[MAX_COMPONENTS];

  671.     int h_count[MAX_COMPONENTS]; /* horizontal and vertical count for each component */

  672.     int v_count[MAX_COMPONENTS];

  673.     int h_max, v_max; /* maximum h and v counts */

  674.     int quant_index[4];   /* quant table index for each component */

  675.     int last_dc[MAX_COMPONENTS]; /* last DEQUANTIZED dc (XXX: am I right to do that ?) */

  676.     uint8_t *current_picture[MAX_COMPONENTS]; /* picture structure */

  677.     int linesize[MAX_COMPONENTS];

  678.     DCTELEM block[64] __align8;

  679.     ScanTable scantable;

  680.     void (*idct_put)(uint8_t *dest/*align 8*/, int line_size, DCTELEM *block/*align 16*/);

  681. 

  682.     int restart_interval;

  683.     int restart_count;

  684. 

  685.     int buggy_avid;

  686.     int interlace_polarity;

  687. } MJpegDecodeContext;

  688. 

  689. static int mjpeg_decode_dht(MJpegDecodeContext *s);

  690. 

  691. static void build_vlc(VLC *vlc, const uint8_t *bits_table, const uint8_t *val_table, 

  692.                       int nb_codes)

  693. {

  694.     uint8_t huff_size[256];

  695.     uint16_t huff_code[256];

  696. 

  697.     memset(huff_size, 0, sizeof(huff_size));

  698.     build_huffman_codes(huff_size, huff_code, bits_table, val_table);

  699.     

  700.     init_vlc(vlc, 9, nb_codes, huff_size, 1, 1, huff_code, 2, 2);

  701. }

  702. 

  703. static int mjpeg_decode_init(AVCodecContext *avctx)

  704. {

  705.     MJpegDecodeContext *s = avctx->priv_data;

  706.     MpegEncContext s2;

  707. 

  708.     s->avctx = avctx;

  709. 

  710.     /* ugly way to get the idct & scantable FIXME */

  711.     memset(&s2, 0, sizeof(MpegEncContext));

  712.     s2.flags= avctx->flags;

  713.     s2.avctx= avctx;

  714. //    s2->out_format = FMT_MJPEG;

  715.     s2.width = 8;

  716.     s2.height = 8;

  717.     if (MPV_common_init(&s2) < 0)

  718.        return -1;

  719.     s->scantable= s2.intra_scantable;

  720.     s->idct_put= s2.dsp.idct_put;

  721.     MPV_common_end(&s2);

  722. 

  723.     s->mpeg_enc_ctx_allocated = 0;

  724.     s->buffer_size = 102400; /* smaller buffer should be enough,

  725. 				but photojpg files could ahive bigger sizes */

  726.     s->buffer = av_malloc(s->buffer_size);

  727.     if (!s->buffer)

  728. 	return -1;

  729.     s->start_code = -1;

  730.     s->first_picture = 1;

  731.     s->org_width = avctx->width;

  732.     s->org_height = avctx->height;

  733.     

  734.     build_vlc(&s->vlcs[0][0], bits_dc_luminance, val_dc_luminance, 12);

  735.     build_vlc(&s->vlcs[0][1], bits_dc_chrominance, val_dc_chrominance, 12);

  736.     build_vlc(&s->vlcs[1][0], bits_ac_luminance, val_ac_luminance, 251);

  737.     build_vlc(&s->vlcs[1][1], bits_ac_chrominance, val_ac_chrominance, 251);

  738. 

  739.     if (avctx->flags & CODEC_FLAG_EXTERN_HUFF)

  740.     {

  741. 	printf("mjpeg: using external huffman table\n");

  742. 	init_get_bits(&s->gb, avctx->extradata, avctx->extradata_size*8);

  743. 	mjpeg_decode_dht(s);

  744. 	/* should check for error - but dunno */

  745.     }

  746. 

  747.     return 0;

  748. }

  749. 

  750. /* quantize tables */

  751. static int mjpeg_decode_dqt(MJpegDecodeContext *s)

  752. {

  753.     int len, index, i, j;

  754.     

  755.     len = get_bits(&s->gb, 16) - 2;

  756. 

  757.     while (len >= 65) {

  758.         /* only 8 bit precision handled */

  759.         if (get_bits(&s->gb, 4) != 0)

  760. 	{

  761. 	    dprintf("dqt: 16bit precision\n");

  762.             return -1;

  763. 	}

  764.         index = get_bits(&s->gb, 4);

  765.         if (index >= 4)

  766.             return -1;

  767.         dprintf("index=%d\n", index);

  768.         /* read quant table */

  769.         for(i=0;i<64;i++) {

  770.             j = s->scantable.permutated[i];

  771. 	    s->quant_matrixes[index][j] = get_bits(&s->gb, 8);

  772.         }

  773.         len -= 65;

  774.     }

  775.     

  776.     return 0;

  777. }

  778. 

  779. /* decode huffman tables and build VLC decoders */

  780. static int mjpeg_decode_dht(MJpegDecodeContext *s)

  781. {

  782.     int len, index, i, class, n, v, code_max;

  783.     uint8_t bits_table[17];

  784.     uint8_t val_table[256];

  785.     

  786.     len = get_bits(&s->gb, 16) - 2;

  787. 

  788.     while (len > 0) {

  789.         if (len < 17)

  790.             return -1;

  791.         class = get_bits(&s->gb, 4);

  792.         if (class >= 2)

  793.             return -1;

  794.         index = get_bits(&s->gb, 4);

  795.         if (index >= 4)

  796.             return -1;

  797.         n = 0;

  798.         for(i=1;i<=16;i++) {

  799.             bits_table[i] = get_bits(&s->gb, 8);

  800.             n += bits_table[i];

  801.         }

  802.         len -= 17;

  803.         if (len < n || n > 256)

  804.             return -1;

  805. 

  806.         code_max = 0;

  807.         for(i=0;i<n;i++) {

  808.             v = get_bits(&s->gb, 8);

  809.             if (v > code_max)

  810.                 code_max = v;

  811.             val_table[i] = v;

  812.         }

  813.         len -= n;

  814. 

  815.         /* build VLC and flush previous vlc if present */

  816.         free_vlc(&s->vlcs[class][index]);

  817.         dprintf("class=%d index=%d nb_codes=%d\n",

  818.                class, index, code_max + 1);

  819.         build_vlc(&s->vlcs[class][index], bits_table, val_table, code_max + 1);

  820.     }

  821.     return 0;

  822. }

  823. 

  824. static int mjpeg_decode_sof0(MJpegDecodeContext *s)

  825. {

  826.     int len, nb_components, i, width, height;

  827. 

  828.     /* XXX: verify len field validity */

  829.     len = get_bits(&s->gb, 16);

  830.     /* only 8 bits/component accepted */

  831.     if (get_bits(&s->gb, 8) != 8)

  832.         return -1;

  833.     height = get_bits(&s->gb, 16);

  834.     width = get_bits(&s->gb, 16);

  835.     dprintf("sof0: picture: %dx%d\n", width, height);

  836. 

  837.     nb_components = get_bits(&s->gb, 8);

  838.     if (nb_components <= 0 ||

  839.         nb_components > MAX_COMPONENTS)

  840.         return -1;

  841.     s->nb_components = nb_components;

  842.     s->h_max = 1;

  843.     s->v_max = 1;

  844.     for(i=0;i<nb_components;i++) {

  845.         /* component id */

  846.         s->component_id[i] = get_bits(&s->gb, 8) - 1;

  847.         s->h_count[i] = get_bits(&s->gb, 4);

  848.         s->v_count[i] = get_bits(&s->gb, 4);

  849.         /* compute hmax and vmax (only used in interleaved case) */

  850.         if (s->h_count[i] > s->h_max)

  851.             s->h_max = s->h_count[i];

  852.         if (s->v_count[i] > s->v_max)

  853.             s->v_max = s->v_count[i];

  854.         s->quant_index[i] = get_bits(&s->gb, 8);

  855.         if (s->quant_index[i] >= 4)

  856.             return -1;

  857.         dprintf("component %d %d:%d id: %d quant:%d\n", i, s->h_count[i],

  858. 	    s->v_count[i], s->component_id[i], s->quant_index[i]);

  859.     }

  860. 

  861.     /* if different size, realloc/alloc picture */

  862.     /* XXX: also check h_count and v_count */

  863.     if (width != s->width || height != s->height) {

  864.         for(i=0;i<MAX_COMPONENTS;i++)

  865.             av_freep(&s->current_picture[i]);

  866.         s->width = width;

  867.         s->height = height;

  868.         /* test interlaced mode */

  869.         if (s->first_picture &&

  870.             s->org_height != 0 &&

  871.             s->height < ((s->org_height * 3) / 4)) {

  872.             s->interlaced = 1;

  873. //	    s->bottom_field = (s->interlace_polarity) ? 1 : 0;

  874. 	    s->bottom_field = 0;

  875.         }

  876. 

  877.         for(i=0;i<nb_components;i++) {

  878.             int w, h;

  879.             w = (s->width  + 8 * s->h_max - 1) / (8 * s->h_max);

  880.             h = (s->height + 8 * s->v_max - 1) / (8 * s->v_max);

  881.             w = w * 8 * s->h_count[i];

  882.             h = h * 8 * s->v_count[i];

  883.             if (s->interlaced)

  884.                 w *= 2;

  885.             s->linesize[i] = w;

  886.             s->current_picture[i] = av_mallocz(w * h);

  887. 	    if (!s->current_picture[i])

  888. 	    {

  889. 		dprintf("error: no picture buffers allocated\n");

  890. 		return -1;

  891. 	    }

  892.         }

  893.         s->first_picture = 0;

  894.     }

  895. 

  896.     if (len != (8+(3*nb_components)))

  897.     {

  898. 	dprintf("decode_sof0: error, len(%d) mismatch\n", len);

  899.     }

  900.     

  901.     return 0;

  902. }

  903. 

  904. static inline int mjpeg_decode_dc(MJpegDecodeContext *s, int dc_index)

  905. {

  906.     int code, diff;

  907. #if 1

  908.     code = get_vlc2(&s->gb, s->vlcs[0][dc_index].table, 9, 2);

  909. #else

  910.     code = get_vlc(&s->gb, &s->vlcs[0][dc_index]);

  911. #endif

  912.     if (code < 0)

  913.     {

  914. 	dprintf("mjpeg_decode_dc: bad vlc: %d:%d (%p)\n", 0, dc_index,

  915.                 &s->vlcs[0][dc_index]);

  916.         return 0xffff;

  917.     }

  918.     if (code == 0) {

  919.         diff = 0;

  920.     } else {

  921.         diff = get_bits(&s->gb, code);

  922.         if ((diff & (1 << (code - 1))) == 0) 

  923.             diff = (-1 << code) | (diff + 1);

  924.     }

  925.     return diff;

  926. }

  927. 

  928. /* decode block and dequantize */

  929. static int decode_block(MJpegDecodeContext *s, DCTELEM *block, 

  930.                         int component, int dc_index, int ac_index, int quant_index)

  931. {

  932.     int nbits, code, i, j, level;

  933.     int run, val;

  934.     VLC *ac_vlc;

  935.     int16_t *quant_matrix;

  936. 

  937.     /* DC coef */

  938.     val = mjpeg_decode_dc(s, dc_index);

  939.     if (val == 0xffff) {

  940.         dprintf("error dc\n");

  941.         return -1;

  942.     }

  943.     quant_matrix = s->quant_matrixes[quant_index];

  944.     val = val * quant_matrix[0] + s->last_dc[component];

  945.     s->last_dc[component] = val;

  946.     block[0] = val;

  947.     /* AC coefs */

  948.     ac_vlc = &s->vlcs[1][ac_index];

  949.     i = 1;

  950.     for(;;) {

  951. #if 1

  952. 	code = get_vlc2(&s->gb, s->vlcs[1][ac_index].table, 9, 2);

  953. #else

  954.         code = get_vlc(&s->gb, ac_vlc);

  955. #endif

  956.         if (code < 0) {

  957.             dprintf("error ac\n");

  958.             return -1;

  959.         }

  960.         /* EOB */

  961.         if (code == 0)

  962.             break;

  963.         if (code == 0xf0) {

  964.             i += 16;

  965.         } else {

  966.             run = code >> 4;

  967.             nbits = code & 0xf;

  968.             level = get_bits(&s->gb, nbits);

  969.             if ((level & (1 << (nbits - 1))) == 0) 

  970.                 level = (-1 << nbits) | (level + 1);

  971.             i += run;

  972.             if (i >= 64) {

  973.                 dprintf("error count: %d\n", i);

  974.                 return -1;

  975.             }

  976.             j = s->scantable.permutated[i];

  977.             block[j] = level * quant_matrix[j];

  978.             i++;

  979.             if (i >= 64)

  980.                 break;

  981.         }

  982.     }

  983.     return 0;

  984. }

  985. 

  986. static int mjpeg_decode_sos(MJpegDecodeContext *s)

  987. {

  988.     int len, nb_components, i, j, n, h, v, ret;

  989.     int mb_width, mb_height, mb_x, mb_y, vmax, hmax, index, id;

  990.     int comp_index[4];

  991.     int dc_index[4];

  992.     int ac_index[4];

  993.     int nb_blocks[4];

  994.     int h_count[4];

  995.     int v_count[4];

  996.     

  997.     /* XXX: verify len field validity */

  998.     len = get_bits(&s->gb, 16);

  999.     nb_components = get_bits(&s->gb, 8);

  1000.     if (len != 6+2*nb_components)

  1001.     {

  1002. 	dprintf("decode_sos: invalid len (%d)\n", len);

  1003. 	return -1;

  1004.     }

  1005.     /* XXX: only interleaved scan accepted */

  1006.     if (nb_components != 3)

  1007.     {

  1008. 	dprintf("decode_sos: components(%d) mismatch\n", nb_components);

  1009.         return -1;

  1010.     }

  1011.     vmax = 0;

  1012.     hmax = 0;

  1013.     for(i=0;i<nb_components;i++) {

  1014.         id = get_bits(&s->gb, 8) - 1;

  1015. 	dprintf("component: %d\n", id);

  1016.         /* find component index */

  1017.         for(index=0;index<s->nb_components;index++)

  1018.             if (id == s->component_id[index])

  1019.                 break;

  1020.         if (index == s->nb_components)

  1021. 	{

  1022. 	    dprintf("decode_sos: index(%d) out of components\n", index);

  1023.             return -1;

  1024. 	}

  1025. 

  1026.         comp_index[i] = index;

  1027.         nb_blocks[i] = s->h_count[index] * s->v_count[index];

  1028.         h_count[i] = s->h_count[index];

  1029.         v_count[i] = s->v_count[index];

  1030. 

  1031.         dc_index[i] = get_bits(&s->gb, 4);

  1032.         ac_index[i] = get_bits(&s->gb, 4);

  1033. 

  1034. 	if (dc_index[i] < 0 || ac_index[i] < 0 ||

  1035. 	    dc_index[i] >= 4 || ac_index[i] >= 4)

  1036. 	    goto out_of_range;

  1037. 	switch(s->start_code)

  1038. 	{

  1039. 	    case SOF0:

  1040. 		if (dc_index[i] > 1 || ac_index[i] > 1)

  1041. 		    goto out_of_range;

  1042. 		break;

  1043. 	    case SOF1:

  1044. 	    case SOF2:

  1045. 		if (dc_index[i] > 3 || ac_index[i] > 3)

  1046. 		    goto out_of_range;

  1047. 		break;

  1048. 	    case SOF3:

  1049. 		if (dc_index[i] > 3 || ac_index[i] != 0)

  1050. 		    goto out_of_range;

  1051. 		break;	

  1052. 	}

  1053.     }

  1054.     skip_bits(&s->gb, 8); /* Ss */

  1055.     skip_bits(&s->gb, 8); /* Se */

  1056.     skip_bits(&s->gb, 8); /* Ah and Al (each are 4 bits) */

  1057. 

  1058.     for(i=0;i<nb_components;i++) 

  1059.         s->last_dc[i] = 1024;

  1060. 

  1061.     if (nb_components > 1) {

  1062.         /* interleaved stream */

  1063.         mb_width = (s->width + s->h_max * 8 - 1) / (s->h_max * 8);

  1064.         mb_height = (s->height + s->v_max * 8 - 1) / (s->v_max * 8);

  1065.     } else {

  1066.         h = s->h_max / s->h_count[comp_index[0]];

  1067.         v = s->v_max / s->v_count[comp_index[0]];

  1068.         mb_width = (s->width + h * 8 - 1) / (h * 8);

  1069.         mb_height = (s->height + v * 8 - 1) / (v * 8);

  1070.         nb_blocks[0] = 1;

  1071.         h_count[0] = 1;

  1072.         v_count[0] = 1;

  1073.     }

  1074.     

  1075.     for(mb_y = 0; mb_y < mb_height; mb_y++) {

  1076.         for(mb_x = 0; mb_x < mb_width; mb_x++) {

  1077.             for(i=0;i<nb_components;i++) {

  1078.                 uint8_t *ptr;

  1079.                 int x, y, c;

  1080.                 n = nb_blocks[i];

  1081.                 c = comp_index[i];

  1082.                 h = h_count[i];

  1083.                 v = v_count[i];

  1084.                 x = 0;

  1085.                 y = 0;

  1086. 		if (s->restart_interval && !s->restart_count)

  1087. 		    s->restart_count = s->restart_interval;

  1088.                 for(j=0;j<n;j++) {

  1089.                     memset(s->block, 0, sizeof(s->block));

  1090.                     if (decode_block(s, s->block, i, 

  1091.                                      dc_index[i], ac_index[i], 

  1092.                                      s->quant_index[c]) < 0) {

  1093.                         dprintf("error y=%d x=%d\n", mb_y, mb_x);

  1094.                         ret = -1;

  1095.                         goto the_end;

  1096.                     }

  1097. //		    dprintf("mb: %d %d processed\n", mb_y, mb_x);

  1098.                     ptr = s->current_picture[c] + 

  1099.                         (s->linesize[c] * (v * mb_y + y) * 8) + 

  1100.                         (h * mb_x + x) * 8;

  1101.                     if (s->interlaced && s->bottom_field)

  1102.                         ptr += s->linesize[c] >> 1;

  1103.                     s->idct_put(ptr, s->linesize[c], s->block);

  1104.                     if (++x == h) {

  1105.                         x = 0;

  1106.                         y++;

  1107.                     }

  1108.                 }

  1109.             }

  1110. 	    /* (< 1350) buggy workaround for Spectralfan.mov, should be fixed */

  1111.             if (s->restart_interval && (s->restart_interval < 1350) &&

  1112. 		!--s->restart_count) {

  1113.                 align_get_bits(&s->gb);

  1114.                 skip_bits(&s->gb, 16); /* skip RSTn */

  1115.                 for (j=0; j<nb_components; j++) /* reset dc */

  1116.                     s->last_dc[j] = 1024;

  1117.             }

  1118.         }

  1119.     }

  1120.     ret = 0;

  1121.  the_end:

  1122.     emms_c();

  1123.     return ret;

  1124.  out_of_range:

  1125.     dprintf("decode_sos: ac/dc index out of range\n");

  1126.     return -1;

  1127. }

  1128. 

  1129. static int mjpeg_decode_dri(MJpegDecodeContext *s)

  1130. {

  1131.     if (get_bits(&s->gb, 16) != 4)

  1132. 	return -1;

  1133.     s->restart_interval = get_bits(&s->gb, 16);

  1134.     dprintf("restart interval: %d\n", s->restart_interval);

  1135. 

  1136.     return 0;

  1137. }

  1138. 

  1139. static int mjpeg_decode_app(MJpegDecodeContext *s)

  1140. {

  1141.     int len, id;

  1142. 

  1143.     /* XXX: verify len field validity */

  1144.     len = get_bits(&s->gb, 16);

  1145.     if (len < 5)

  1146. 	return -1;

  1147. 

  1148.     id = (get_bits(&s->gb, 16) << 16) | get_bits(&s->gb, 16);

  1149.     id = be2me_32(id);

  1150.     len -= 6;

  1151. 

  1152.     /* buggy AVID, it puts EOI only at every 10th frame */

  1153.     /* also this fourcc is used by non-avid files too, it holds some

  1154.        informations, but it's always present in AVID creates files */

  1155.     if (id == ff_get_fourcc("AVI1"))

  1156.     {

  1157. 	/* structure:

  1158. 	    4bytes	AVI1

  1159. 	    1bytes	polarity

  1160. 	    1bytes	always zero

  1161. 	    4bytes	field_size

  1162. 	    4bytes	field_size_less_padding

  1163. 	*/

  1164.     	s->buggy_avid = 1;

  1165. //	if (s->first_picture)

  1166. //	    printf("mjpeg: workarounding buggy AVID\n");

  1167. 	s->interlace_polarity = get_bits(&s->gb, 8);

  1168. #if 0

  1169. 	skip_bits(&s->gb, 8);

  1170. 	skip_bits(&s->gb, 32);

  1171. 	skip_bits(&s->gb, 32);

  1172. 	len -= 10;

  1173. #endif

  1174. //	if (s->interlace_polarity)

  1175. //	    printf("mjpeg: interlace polarity: %d\n", s->interlace_polarity);

  1176. 	goto out;

  1177.     }

  1178.     

  1179. //    len -= 2;

  1180.     

  1181.     if (id == ff_get_fourcc("JFIF"))

  1182.     {

  1183. 	int t_w, t_h;

  1184. 	skip_bits(&s->gb, 8); /* the trailing zero-byte */

  1185. 	printf("mjpeg: JFIF header found (version: %x.%x)\n",

  1186. 	    get_bits(&s->gb, 8), get_bits(&s->gb, 8));

  1187. 	if (get_bits(&s->gb, 8) == 0)

  1188. 	{

  1189. 	    int x_density, y_density; 

  1190. 	    x_density = get_bits(&s->gb, 16);

  1191. 	    y_density = get_bits(&s->gb, 16);

  1192. 

  1193. 	    dprintf("x/y density: %d (%f), %d (%f)\n", x_density,

  1194. 		(float)x_density, y_density, (float)y_density);

  1195. #if 0

  1196.             //MN: needs to be checked

  1197.             if(x_density)

  1198. //                s->avctx->aspect_ratio= s->width*y_density/((float)s->height*x_density);

  1199. 		s->avctx->aspect_ratio = (float)x_density/y_density;

  1200. 		/* it's better, but every JFIF I have seen stores 1:1 */

  1201.             else

  1202.                 s->avctx->aspect_ratio= 0.0;

  1203. #endif

  1204. 	}

  1205. 	else

  1206. 	{

  1207. 	    skip_bits(&s->gb, 16);

  1208. 	    skip_bits(&s->gb, 16);

  1209. 	}

  1210. 

  1211. 	t_w = get_bits(&s->gb, 8);

  1212. 	t_h = get_bits(&s->gb, 8);

  1213. 	if (t_w && t_h)

  1214. 	{

  1215. 	    /* skip thumbnail */

  1216. 	    if (len-10-(t_w*t_h*3) > 0)

  1217. 		len -= t_w*t_h*3;

  1218. 	}

  1219. 	len -= 10;

  1220. 	goto out;

  1221.     }

  1222.     

  1223.     if (id == ff_get_fourcc("Adob") && (get_bits(&s->gb, 8) == 'e'))

  1224.     {

  1225. 	printf("mjpeg: Adobe header found\n");

  1226. 	skip_bits(&s->gb, 16); /* version */

  1227. 	skip_bits(&s->gb, 16); /* flags0 */

  1228. 	skip_bits(&s->gb, 16); /* flags1 */

  1229. 	skip_bits(&s->gb, 8); /* transform */

  1230. 	len -= 7;

  1231. 	goto out;

  1232.     }

  1233.     

  1234.     /* Apple MJPEG-A */

  1235.     if ((s->start_code == APP1) && (len > (0x28 - 8)))

  1236.     {

  1237. 	id = (get_bits(&s->gb, 16) << 16) | get_bits(&s->gb, 16);

  1238. 	id = be2me_32(id);

  1239. 	len -= 4;

  1240. 	if (id == ff_get_fourcc("mjpg")) /* Apple MJPEG-A */

  1241. 	{

  1242. #if 0

  1243. 	    skip_bits(&s->gb, 32); /* field size */

  1244. 	    skip_bits(&s->gb, 32); /* pad field size */

  1245. 	    skip_bits(&s->gb, 32); /* next off */

  1246. 	    skip_bits(&s->gb, 32); /* quant off */

  1247. 	    skip_bits(&s->gb, 32); /* huff off */

  1248. 	    skip_bits(&s->gb, 32); /* image off */

  1249. 	    skip_bits(&s->gb, 32); /* scan off */

  1250. 	    skip_bits(&s->gb, 32); /* data off */

  1251. #endif

  1252. 	    if (s->first_picture)

  1253. 		printf("mjpeg: Apple MJPEG-A header found\n");

  1254. 	}

  1255.     }

  1256. 

  1257. out:

  1258.     /* slow but needed for extreme adobe jpegs */

  1259.     if (len < 0)

  1260. 	printf("mjpeg: error, decode_app parser read over the end\n");

  1261.     while(--len > 0)

  1262. 	skip_bits(&s->gb, 8);

  1263. 

  1264.     return 0;

  1265. }

  1266. 

  1267. static int mjpeg_decode_com(MJpegDecodeContext *s)

  1268. {

  1269.     /* XXX: verify len field validity */

  1270.     unsigned int len = get_bits(&s->gb, 16);

  1271.     if (len >= 2 && len < 32768) {

  1272. 	/* XXX: any better upper bound */

  1273. 	uint8_t *cbuf = av_malloc(len - 1);

  1274. 	if (cbuf) {

  1275. 	    int i;

  1276. 	    for (i = 0; i < len - 2; i++)

  1277. 		cbuf[i] = get_bits(&s->gb, 8);

  1278. 	    if (i > 0 && cbuf[i-1] == '\n')

  1279. 		cbuf[i-1] = 0;

  1280. 	    else

  1281. 		cbuf[i] = 0;

  1282. 

  1283. 	    printf("mjpeg comment: '%s'\n", cbuf);

  1284. 

  1285. 	    /* buggy avid, it puts EOI only at every 10th frame */

  1286. 	    if (!strcmp(cbuf, "AVID"))

  1287. 	    {

  1288. 		s->buggy_avid = 1;

  1289. 		//	if (s->first_picture)

  1290. 		//	    printf("mjpeg: workarounding buggy AVID\n");

  1291. 	    }

  1292. 

  1293. 	    av_free(cbuf);

  1294. 	}

  1295.     }

  1296. 

  1297.     return 0;

  1298. }

  1299. 

  1300. #if 0

  1301. static int valid_marker_list[] =

  1302. {

  1303.         /* 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, f */

  1304. /* 0 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1305. /* 1 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1306. /* 2 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1307. /* 3 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1308. /* 4 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1309. /* 5 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1310. /* 6 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1311. /* 7 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1312. /* 8 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1313. /* 9 */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1314. /* a */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1315. /* b */    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,

  1316. /* c */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1317. /* d */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1318. /* e */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,

  1319. /* f */    1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0,

  1320. }

  1321. #endif

  1322. 

  1323. /* return the 8 bit start code value and update the search

  1324.    state. Return -1 if no start code found */

  1325. static int find_marker(uint8_t **pbuf_ptr, uint8_t *buf_end)

  1326. {

  1327.     uint8_t *buf_ptr;

  1328.     unsigned int v, v2;

  1329.     int val;

  1330. #ifdef DEBUG

  1331.     int skipped=0;

  1332. #endif

  1333. 

  1334.     buf_ptr = *pbuf_ptr;

  1335.     while (buf_ptr < buf_end) {

  1336.         v = *buf_ptr++;

  1337. 	v2 = *buf_ptr;

  1338.         if ((v == 0xff) && (v2 >= 0xc0) && (v2 <= 0xfe)) {

  1339. 	    val = *buf_ptr++;

  1340. 	    goto found;

  1341.         }

  1342. #ifdef DEBUG

  1343. 	skipped++;

  1344. #endif

  1345.     }

  1346.     val = -1;

  1347. found:

  1348. #ifdef DEBUG

  1349.     dprintf("find_marker skipped %d bytes\n", skipped);

  1350. #endif

  1351.     *pbuf_ptr = buf_ptr;

  1352.     return val;

  1353. }

  1354. 

  1355. static int mjpeg_decode_frame(AVCodecContext *avctx, 

  1356.                               void *data, int *data_size,

  1357.                               uint8_t *buf, int buf_size)

  1358. {

  1359.     MJpegDecodeContext *s = avctx->priv_data;

  1360.     uint8_t *buf_end, *buf_ptr;

  1361.     int i, start_code;

  1362.     AVPicture *picture = data;

  1363. 

  1364.     *data_size = 0;

  1365. 

  1366.     /* no supplementary picture */

  1367.     if (buf_size == 0)

  1368.         return 0;

  1369. 

  1370.     buf_ptr = buf;

  1371.     buf_end = buf + buf_size;

  1372.     while (buf_ptr < buf_end) {

  1373.         /* find start next marker */

  1374.         start_code = find_marker(&buf_ptr, buf_end);

  1375. 	{

  1376. 	    /* EOF */

  1377.             if (start_code < 0) {

  1378. 		goto the_end;

  1379.             } else {

  1380.                 dprintf("marker=%x avail_size_in_buf=%d\n", start_code, buf_end - buf_ptr);

  1381. 		

  1382. 		if ((buf_end - buf_ptr) > s->buffer_size)

  1383. 		{

  1384. 		    av_free(s->buffer);

  1385. 		    s->buffer_size = buf_end-buf_ptr;

  1386. 		    s->buffer = av_malloc(s->buffer_size);

  1387. 		    dprintf("buffer too small, expanding to %d bytes\n",

  1388. 			s->buffer_size);

  1389. 		}

  1390. 		

  1391. 		/* unescape buffer of SOS */

  1392. 		if (start_code == SOS)

  1393. 		{

  1394. 		    uint8_t *src = buf_ptr;

  1395. 		    uint8_t *dst = s->buffer;

  1396. 

  1397. 		    while (src<buf_end)

  1398. 		    {

  1399. 			uint8_t x = *(src++);

  1400. 

  1401. 			*(dst++) = x;

  1402. 			if (x == 0xff)

  1403. 			{

  1404. 			    while(*src == 0xff) src++;

  1405. 

  1406. 			    x = *(src++);

  1407. 			    if (x >= 0xd0 && x <= 0xd7)

  1408. 				*(dst++) = x;

  1409. 			    else if (x)

  1410. 				break;

  1411. 			}

  1412. 		    }

  1413. 		    init_get_bits(&s->gb, s->buffer, (dst - s->buffer)*8);

  1414. 		    

  1415. 		    dprintf("escaping removed %d bytes\n",

  1416. 			(buf_end - buf_ptr) - (dst - s->buffer));

  1417. 		}

  1418. 		else

  1419. 		    init_get_bits(&s->gb, buf_ptr, (buf_end - buf_ptr)*8);

  1420. 		

  1421. 		s->start_code = start_code;

  1422. 

  1423. 		/* process markers */

  1424. 		if (start_code >= 0xd0 && start_code <= 0xd7) {

  1425. 		    dprintf("restart marker: %d\n", start_code&0x0f);

  1426. 		} else if (s->first_picture) {

  1427. 		    /* APP fields */

  1428. 		    if (start_code >= 0xe0 && start_code <= 0xef)

  1429. 			mjpeg_decode_app(s);

  1430. 		    /* Comment */

  1431. 		    else if (start_code == COM)

  1432. 			mjpeg_decode_com(s);

  1433. 		}

  1434. 

  1435.                 switch(start_code) {

  1436.                 case SOI:

  1437. 		    s->restart_interval = 0;

  1438.                     /* nothing to do on SOI */

  1439.                     break;

  1440.                 case DQT:

  1441.                     mjpeg_decode_dqt(s);

  1442.                     break;

  1443.                 case DHT:

  1444.                     mjpeg_decode_dht(s);

  1445.                     break;

  1446.                 case SOF0:

  1447.                     if (mjpeg_decode_sof0(s) < 0)

  1448. 			return -1;

  1449.                     break;

  1450. 		case EOI:

  1451. eoi_parser:

  1452. 		    {

  1453.                         if (s->interlaced) {

  1454.                             s->bottom_field ^= 1;

  1455.                             /* if not bottom field, do not output image yet */

  1456.                             if (s->bottom_field)

  1457.                                 goto not_the_end;

  1458.                         }

  1459.                         for(i=0;i<3;i++) {

  1460.                             picture->data[i] = s->current_picture[i];

  1461. 			    picture->linesize[i] = (s->interlaced) ?

  1462. 				s->linesize[i] >> 1 : s->linesize[i];

  1463.                         }

  1464.                         *data_size = sizeof(AVPicture);

  1465.                         avctx->height = s->height;

  1466.                         if (s->interlaced)

  1467.                             avctx->height *= 2;

  1468.                         avctx->width = s->width;

  1469.                         /* XXX: not complete test ! */

  1470.                         switch((s->h_count[0] << 4) | s->v_count[0]) {

  1471.                         case 0x11:

  1472.                             avctx->pix_fmt = PIX_FMT_YUV444P;

  1473.                             break;

  1474.                         case 0x21:

  1475.                             avctx->pix_fmt = PIX_FMT_YUV422P;

  1476.                             break;

  1477.                         default:

  1478.                         case 0x22:

  1479.                             avctx->pix_fmt = PIX_FMT_YUV420P;

  1480.                             break;

  1481.                         }

  1482.                         /* dummy quality */

  1483.                         /* XXX: infer it with matrix */

  1484. //                    	avctx->quality = 3; 

  1485.                         goto the_end;

  1486.                     }

  1487. 		    break;

  1488.                 case SOS:

  1489.                     mjpeg_decode_sos(s);

  1490. 		    /* buggy avid puts EOI every 10-20th frame */

  1491. 		    /* if restart period is over process EOI */

  1492. 		    if ((s->buggy_avid && !s->interlaced) || s->restart_interval)

  1493. 			goto eoi_parser;

  1494.                     break;

  1495. 		case DRI:

  1496. 		    mjpeg_decode_dri(s);

  1497. 		    break;

  1498. 		case SOF1:

  1499. 		case SOF2:

  1500. 		case SOF3:

  1501. 		case SOF5:

  1502. 		case SOF6:

  1503. 		case SOF7:

  1504. 		case SOF9:

  1505. 		case SOF10:

  1506. 		case SOF11:

  1507. 		case SOF13:

  1508. 		case SOF14:

  1509. 		case SOF15:

  1510. 		case JPG:

  1511. 		    printf("mjpeg: unsupported coding type (%x)\n", start_code);

  1512. 		    break;

  1513. //		default:

  1514. //		    printf("mjpeg: unsupported marker (%x)\n", start_code);

  1515. //		    break;

  1516.                 }

  1517. 

  1518. not_the_end:

  1519. 		/* eof process start code */

  1520. 		buf_ptr += (get_bits_count(&s->gb)+7)/8;

  1521. 		dprintf("marker parser used %d bytes (%d bits)\n",

  1522. 		    (get_bits_count(&s->gb)+7)/8, get_bits_count(&s->gb));

  1523.             }

  1524.         }

  1525.     }

  1526. the_end:

  1527.     dprintf("mjpeg decode frame unused %d bytes\n", buf_end - buf_ptr);

  1528. //    return buf_end - buf_ptr;

  1529.     return buf_ptr - buf;

  1530. }

  1531. 

  1532. static int mjpegb_decode_frame(AVCodecContext *avctx, 

  1533.                               void *data, int *data_size,

  1534.                               uint8_t *buf, int buf_size)

  1535. {

  1536.     MJpegDecodeContext *s = avctx->priv_data;

  1537.     uint8_t *buf_end, *buf_ptr;

  1538.     int i;

  1539.     AVPicture *picture = data;

  1540.     GetBitContext hgb; /* for the header */

  1541.     uint32_t dqt_offs, dht_offs, sof_offs, sos_offs, second_field_offs;

  1542.     uint32_t field_size;

  1543. 

  1544.     *data_size = 0;

  1545. 

  1546.     /* no supplementary picture */

  1547.     if (buf_size == 0)

  1548.         return 0;

  1549. 

  1550.     buf_ptr = buf;

  1551.     buf_end = buf + buf_size;

  1552.     

  1553. read_header:

  1554.     /* reset on every SOI */

  1555.     s->restart_interval = 0;

  1556. 

  1557.     init_get_bits(&hgb, buf_ptr, /*buf_size*/(buf_end - buf_ptr)*8);

  1558. 

  1559.     skip_bits(&hgb, 32); /* reserved zeros */

  1560.     

  1561.     if (get_bits(&hgb, 32) != be2me_32(ff_get_fourcc("mjpg")))

  1562.     {

  1563. 	dprintf("not mjpeg-b (bad fourcc)\n");

  1564. 	return 0;

  1565.     }

  1566. 

  1567.     field_size = get_bits(&hgb, 32); /* field size */

  1568.     dprintf("field size: 0x%x\n", field_size);

  1569.     skip_bits(&hgb, 32); /* padded field size */

  1570.     second_field_offs = get_bits(&hgb, 32);

  1571.     dprintf("second field offs: 0x%x\n", second_field_offs);

  1572.     if (second_field_offs)

  1573. 	s->interlaced = 1;

  1574. 

  1575.     dqt_offs = get_bits(&hgb, 32);

  1576.     dprintf("dqt offs: 0x%x\n", dqt_offs);

  1577.     if (dqt_offs)

  1578.     {

  1579. 	init_get_bits(&s->gb, buf+dqt_offs, (buf_end - (buf+dqt_offs))*8);

  1580. 	s->start_code = DQT;

  1581. 	mjpeg_decode_dqt(s);

  1582.     }

  1583.     

  1584.     dht_offs = get_bits(&hgb, 32);

  1585.     dprintf("dht offs: 0x%x\n", dht_offs);

  1586.     if (dht_offs)

  1587.     {

  1588. 	init_get_bits(&s->gb, buf+dht_offs, (buf_end - (buf+dht_offs))*8);

  1589. 	s->start_code = DHT;

  1590. 	mjpeg_decode_dht(s);

  1591.     }

  1592. 

  1593.     sof_offs = get_bits(&hgb, 32);

  1594.     dprintf("sof offs: 0x%x\n", sof_offs);

  1595.     if (sof_offs)

  1596.     {

  1597. 	init_get_bits(&s->gb, buf+sof_offs, (buf_end - (buf+sof_offs))*8);

  1598. 	s->start_code = SOF0;

  1599. 	if (mjpeg_decode_sof0(s) < 0)

  1600. 	    return -1;

  1601.     }

  1602. 

  1603.     sos_offs = get_bits(&hgb, 32);

  1604.     dprintf("sos offs: 0x%x\n", sos_offs);

  1605.     if (sos_offs)

  1606.     {

  1607. //	init_get_bits(&s->gb, buf+sos_offs, (buf_end - (buf+sos_offs))*8);

  1608. 	init_get_bits(&s->gb, buf+sos_offs, field_size*8);

  1609. 	s->start_code = SOS;

  1610. 	mjpeg_decode_sos(s);

  1611.     }

  1612. 

  1613.     skip_bits(&hgb, 32); /* start of data offset */

  1614. 

  1615.     if (s->interlaced) {

  1616.         s->bottom_field ^= 1;

  1617.         /* if not bottom field, do not output image yet */

  1618.         if (s->bottom_field && second_field_offs)

  1619. 	{

  1620. 	    buf_ptr = buf + second_field_offs;

  1621. 	    second_field_offs = 0;

  1622. 	    goto read_header;

  1623.     	}

  1624.     }

  1625. 

  1626.     for(i=0;i<3;i++) {

  1627.         picture->data[i] = s->current_picture[i];

  1628.         picture->linesize[i] = (s->interlaced) ?

  1629.     	    s->linesize[i] >> 1 : s->linesize[i];

  1630.     }

  1631.     *data_size = sizeof(AVPicture);

  1632.     avctx->height = s->height;

  1633.     if (s->interlaced)

  1634.         avctx->height *= 2;

  1635.     avctx->width = s->width;

  1636.     /* XXX: not complete test ! */

  1637.     switch((s->h_count[0] << 4) | s->v_count[0]) {

  1638.         case 0x11:

  1639.     	    avctx->pix_fmt = PIX_FMT_YUV444P;

  1640.             break;

  1641.         case 0x21:

  1642.             avctx->pix_fmt = PIX_FMT_YUV422P;

  1643.             break;

  1644.         default:

  1645. 	case 0x22:

  1646.             avctx->pix_fmt = PIX_FMT_YUV420P;

  1647.             break;

  1648.     }

  1649.     /* dummy quality */

  1650.     /* XXX: infer it with matrix */

  1651. //    avctx->quality = 3; 

  1652. 

  1653.     return buf_ptr - buf;

  1654. }

  1655. 

  1656. 

  1657. static int mjpeg_decode_end(AVCodecContext *avctx)

  1658. {

  1659.     MJpegDecodeContext *s = avctx->priv_data;

  1660.     int i, j;

  1661. 

  1662.     av_free(s->buffer);

  1663.     for(i=0;i<MAX_COMPONENTS;i++)

  1664.         av_free(s->current_picture[i]);

  1665.     for(i=0;i<2;i++) {

  1666.         for(j=0;j<4;j++)

  1667.             free_vlc(&s->vlcs[i][j]);

  1668.     }

  1669.     return 0;

  1670. }

  1671. 

  1672. AVCodec mjpeg_decoder = {

  1673.     "mjpeg",

  1674.     CODEC_TYPE_VIDEO,

  1675.     CODEC_ID_MJPEG,

  1676.     sizeof(MJpegDecodeContext),

  1677.     mjpeg_decode_init,

  1678.     NULL,

  1679.     mjpeg_decode_end,

  1680.     mjpeg_decode_frame,

  1681.     0,

  1682.     NULL

  1683. };

  1684. 

  1685. AVCodec mjpegb_decoder = {

  1686.     "mjpegb",

  1687.     CODEC_TYPE_VIDEO,

  1688.     CODEC_ID_MJPEGB,

  1689.     sizeof(MJpegDecodeContext),

  1690.     mjpeg_decode_init,

  1691.     NULL,

  1692.     mjpeg_decode_end,

  1693.     mjpegb_decode_frame,

  1694.     0,

  1695.     NULL

  1696. };