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FFmpeg/libavcodec/dvbsubdec.c

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  1. /*

  2.  * DVB subtitle decoding for ffmpeg

  3.  * Copyright (c) 2005 Ian Caulfield.

  4.  *

  5.  * This file is part of FFmpeg.

  6.  *

  7.  * FFmpeg is free software; you can redistribute it and/or

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

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

  10.  * version 2.1 of the License, or (at your option) any later version.

  11.  *

  12.  * FFmpeg is distributed in the hope that it will be useful,

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

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

  15.  * Lesser General Public License for more details.

  16.  *

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

  18.  * License along with FFmpeg; if not, write to the Free Software

  19.  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

  20.  */

  21. #include "avcodec.h"

  22. #include "dsputil.h"

  23. #include "bitstream.h"

  24. #include "colorspace.h"

  25. 

  26. //#define DEBUG

  27. //#define DEBUG_PACKET_CONTENTS

  28. //#define DEBUG_SAVE_IMAGES

  29. 

  30. #define DVBSUB_PAGE_SEGMENT     0x10

  31. #define DVBSUB_REGION_SEGMENT   0x11

  32. #define DVBSUB_CLUT_SEGMENT     0x12

  33. #define DVBSUB_OBJECT_SEGMENT   0x13

  34. #define DVBSUB_DISPLAY_SEGMENT  0x80

  35. 

  36. #define cm (ff_cropTbl + MAX_NEG_CROP)

  37. 

  38. #ifdef DEBUG_SAVE_IMAGES

  39. #undef fprintf

  40. #if 0

  41. static void png_save(const char *filename, uint8_t *bitmap, int w, int h,

  42.                      uint32_t *rgba_palette)

  43. {

  44.     int x, y, v;

  45.     FILE *f;

  46.     char fname[40], fname2[40];

  47.     char command[1024];

  48. 

  49.     snprintf(fname, 40, "%s.ppm", filename);

  50. 

  51.     f = fopen(fname, "w");

  52.     if (!f) {

  53.         perror(fname);

  54.         exit(1);

  55.     }

  56.     fprintf(f, "P6\n"

  57.             "%d %d\n"

  58.             "%d\n",

  59.             w, h, 255);

  60.     for(y = 0; y < h; y++) {

  61.         for(x = 0; x < w; x++) {

  62.             v = rgba_palette[bitmap[y * w + x]];

  63.             putc((v >> 16) & 0xff, f);

  64.             putc((v >> 8) & 0xff, f);

  65.             putc((v >> 0) & 0xff, f);

  66.         }

  67.     }

  68.     fclose(f);

  69. 

  70. 

  71.     snprintf(fname2, 40, "%s-a.pgm", filename);

  72. 

  73.     f = fopen(fname2, "w");

  74.     if (!f) {

  75.         perror(fname2);

  76.         exit(1);

  77.     }

  78.     fprintf(f, "P5\n"

  79.             "%d %d\n"

  80.             "%d\n",

  81.             w, h, 255);

  82.     for(y = 0; y < h; y++) {

  83.         for(x = 0; x < w; x++) {

  84.             v = rgba_palette[bitmap[y * w + x]];

  85.             putc((v >> 24) & 0xff, f);

  86.         }

  87.     }

  88.     fclose(f);

  89. 

  90.     snprintf(command, 1024, "pnmtopng -alpha %s %s > %s.png 2> /dev/null", fname2, fname, filename);

  91.     system(command);

  92. 

  93.     snprintf(command, 1024, "rm %s %s", fname, fname2);

  94.     system(command);

  95. }

  96. #endif

  97. 

  98. static void png_save2(const char *filename, uint32_t *bitmap, int w, int h)

  99. {

  100.     int x, y, v;

  101.     FILE *f;

  102.     char fname[40], fname2[40];

  103.     char command[1024];

  104. 

  105.     snprintf(fname, sizeof(fname), "%s.ppm", filename);

  106. 

  107.     f = fopen(fname, "w");

  108.     if (!f) {

  109.         perror(fname);

  110.         exit(1);

  111.     }

  112.     fprintf(f, "P6\n"

  113.             "%d %d\n"

  114.             "%d\n",

  115.             w, h, 255);

  116.     for(y = 0; y < h; y++) {

  117.         for(x = 0; x < w; x++) {

  118.             v = bitmap[y * w + x];

  119.             putc((v >> 16) & 0xff, f);

  120.             putc((v >> 8) & 0xff, f);

  121.             putc((v >> 0) & 0xff, f);

  122.         }

  123.     }

  124.     fclose(f);

  125. 

  126. 

  127.     snprintf(fname2, sizeof(fname2), "%s-a.pgm", filename);

  128. 

  129.     f = fopen(fname2, "w");

  130.     if (!f) {

  131.         perror(fname2);

  132.         exit(1);

  133.     }

  134.     fprintf(f, "P5\n"

  135.             "%d %d\n"

  136.             "%d\n",

  137.             w, h, 255);

  138.     for(y = 0; y < h; y++) {

  139.         for(x = 0; x < w; x++) {

  140.             v = bitmap[y * w + x];

  141.             putc((v >> 24) & 0xff, f);

  142.         }

  143.     }

  144.     fclose(f);

  145. 

  146.     snprintf(command, sizeof(command), "pnmtopng -alpha %s %s > %s.png 2> /dev/null", fname2, fname, filename);

  147.     system(command);

  148. 

  149.     snprintf(command, sizeof(command), "rm %s %s", fname, fname2);

  150.     system(command);

  151. }

  152. #endif

  153. 

  154. #define RGBA(r,g,b,a) (((a) << 24) | ((r) << 16) | ((g) << 8) | (b))

  155. 

  156. typedef struct DVBSubCLUT {

  157.     int id;

  158. 

  159.     uint32_t clut4[4];

  160.     uint32_t clut16[16];

  161.     uint32_t clut256[256];

  162. 

  163.     struct DVBSubCLUT *next;

  164. } DVBSubCLUT;

  165. 

  166. static DVBSubCLUT default_clut;

  167. 

  168. typedef struct DVBSubObjectDisplay {

  169.     int object_id;

  170.     int region_id;

  171. 

  172.     int x_pos;

  173.     int y_pos;

  174. 

  175.     int fgcolor;

  176.     int bgcolor;

  177. 

  178.     struct DVBSubObjectDisplay *region_list_next;

  179.     struct DVBSubObjectDisplay *object_list_next;

  180. } DVBSubObjectDisplay;

  181. 

  182. typedef struct DVBSubObject {

  183.     int id;

  184. 

  185.     int type;

  186. 

  187.     DVBSubObjectDisplay *display_list;

  188. 

  189.     struct DVBSubObject *next;

  190. } DVBSubObject;

  191. 

  192. typedef struct DVBSubRegionDisplay {

  193.     int region_id;

  194. 

  195.     int x_pos;

  196.     int y_pos;

  197. 

  198.     struct DVBSubRegionDisplay *next;

  199. } DVBSubRegionDisplay;

  200. 

  201. typedef struct DVBSubRegion {

  202.     int id;

  203. 

  204.     int width;

  205.     int height;

  206.     int depth;

  207. 

  208.     int clut;

  209.     int bgcolor;

  210. 

  211.     uint8_t *pbuf;

  212.     int buf_size;

  213. 

  214.     DVBSubObjectDisplay *display_list;

  215. 

  216.     struct DVBSubRegion *next;

  217. } DVBSubRegion;

  218. 

  219. typedef struct DVBSubContext {

  220.     int composition_id;

  221.     int ancillary_id;

  222. 

  223.     int time_out;

  224.     DVBSubRegion *region_list;

  225.     DVBSubCLUT   *clut_list;

  226.     DVBSubObject *object_list;

  227. 

  228.     int display_list_size;

  229.     DVBSubRegionDisplay *display_list;

  230. } DVBSubContext;

  231. 

  232. 

  233. static DVBSubObject* get_object(DVBSubContext *ctx, int object_id)

  234. {

  235.     DVBSubObject *ptr = ctx->object_list;

  236. 

  237.     while (ptr && ptr->id != object_id) {

  238.         ptr = ptr->next;

  239.     }

  240. 

  241.     return ptr;

  242. }

  243. 

  244. static DVBSubCLUT* get_clut(DVBSubContext *ctx, int clut_id)

  245. {

  246.     DVBSubCLUT *ptr = ctx->clut_list;

  247. 

  248.     while (ptr && ptr->id != clut_id) {

  249.         ptr = ptr->next;

  250.     }

  251. 

  252.     return ptr;

  253. }

  254. 

  255. static DVBSubRegion* get_region(DVBSubContext *ctx, int region_id)

  256. {

  257.     DVBSubRegion *ptr = ctx->region_list;

  258. 

  259.     while (ptr && ptr->id != region_id) {

  260.         ptr = ptr->next;

  261.     }

  262. 

  263.     return ptr;

  264. }

  265. 

  266. static void delete_region_display_list(DVBSubContext *ctx, DVBSubRegion *region)

  267. {

  268.     DVBSubObject *object, *obj2, **obj2_ptr;

  269.     DVBSubObjectDisplay *display, *obj_disp, **obj_disp_ptr;

  270. 

  271.     while (region->display_list) {

  272.         display = region->display_list;

  273. 

  274.         object = get_object(ctx, display->object_id);

  275. 

  276.         if (object) {

  277.             obj_disp = object->display_list;

  278.             obj_disp_ptr = &object->display_list;

  279. 

  280.             while (obj_disp && obj_disp != display) {

  281.                 obj_disp_ptr = &obj_disp->object_list_next;

  282.                 obj_disp = obj_disp->object_list_next;

  283.             }

  284. 

  285.             if (obj_disp) {

  286.                 *obj_disp_ptr = obj_disp->object_list_next;

  287. 

  288.                 if (!object->display_list) {

  289.                     obj2 = ctx->object_list;

  290.                     obj2_ptr = &ctx->object_list;

  291. 

  292.                     while (obj2 && obj2 != object) {

  293.                         obj2_ptr = &obj2->next;

  294.                         obj2 = obj2->next;

  295.                     }

  296. 

  297.                     *obj2_ptr = obj2->next;

  298. 

  299.                     av_free(obj2);

  300.                 }

  301.             }

  302.         }

  303. 

  304.         region->display_list = display->region_list_next;

  305. 

  306.         av_free(display);

  307.     }

  308. 

  309. }

  310. 

  311. static void delete_state(DVBSubContext *ctx)

  312. {

  313.     DVBSubRegion *region;

  314.     DVBSubCLUT *clut;

  315. 

  316.     while (ctx->region_list) {

  317.         region = ctx->region_list;

  318. 

  319.         ctx->region_list = region->next;

  320. 

  321.         delete_region_display_list(ctx, region);

  322.         if (region->pbuf)

  323.             av_free(region->pbuf);

  324. 

  325.         av_free(region);

  326.     }

  327. 

  328.     while (ctx->clut_list) {

  329.         clut = ctx->clut_list;

  330. 

  331.         ctx->clut_list = clut->next;

  332. 

  333.         av_free(clut);

  334.     }

  335. 

  336.     /* Should already be null */

  337.     if (ctx->object_list)

  338.         av_log(0, AV_LOG_ERROR, "Memory deallocation error!\n");

  339. }

  340. 

  341. static int dvbsub_init_decoder(AVCodecContext *avctx)

  342. {

  343.     int i, r, g, b, a = 0;

  344.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  345. 

  346.     memset(avctx->priv_data, 0, sizeof(DVBSubContext));

  347. 

  348.     ctx->composition_id = avctx->sub_id & 0xffff;

  349.     ctx->ancillary_id = avctx->sub_id >> 16;

  350. 

  351.     default_clut.id = -1;

  352.     default_clut.next = NULL;

  353. 

  354.     default_clut.clut4[0] = RGBA(  0,   0,   0,   0);

  355.     default_clut.clut4[1] = RGBA(255, 255, 255, 255);

  356.     default_clut.clut4[2] = RGBA(  0,   0,   0, 255);

  357.     default_clut.clut4[3] = RGBA(127, 127, 127, 255);

  358. 

  359.     default_clut.clut16[0] = RGBA(  0,   0,   0,   0);

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

  361.         if (i < 8) {

  362.             r = (i & 1) ? 255 : 0;

  363.             g = (i & 2) ? 255 : 0;

  364.             b = (i & 4) ? 255 : 0;

  365.         } else {

  366.             r = (i & 1) ? 127 : 0;

  367.             g = (i & 2) ? 127 : 0;

  368.             b = (i & 4) ? 127 : 0;

  369.         }

  370.         default_clut.clut16[i] = RGBA(r, g, b, 255);

  371.     }

  372. 

  373.     default_clut.clut256[0] = RGBA(  0,   0,   0,   0);

  374.     for (i = 1; i < 256; i++) {

  375.         if (i < 8) {

  376.             r = (i & 1) ? 255 : 0;

  377.             g = (i & 2) ? 255 : 0;

  378.             b = (i & 4) ? 255 : 0;

  379.             a = 63;

  380.         } else {

  381.             switch (i & 0x88) {

  382.             case 0x00:

  383.                 r = ((i & 1) ? 85 : 0) + ((i & 0x10) ? 170 : 0);

  384.                 g = ((i & 2) ? 85 : 0) + ((i & 0x20) ? 170 : 0);

  385.                 b = ((i & 4) ? 85 : 0) + ((i & 0x40) ? 170 : 0);

  386.                 a = 255;

  387.                 break;

  388.             case 0x08:

  389.                 r = ((i & 1) ? 85 : 0) + ((i & 0x10) ? 170 : 0);

  390.                 g = ((i & 2) ? 85 : 0) + ((i & 0x20) ? 170 : 0);

  391.                 b = ((i & 4) ? 85 : 0) + ((i & 0x40) ? 170 : 0);

  392.                 a = 127;

  393.                 break;

  394.             case 0x80:

  395.                 r = 127 + ((i & 1) ? 43 : 0) + ((i & 0x10) ? 85 : 0);

  396.                 g = 127 + ((i & 2) ? 43 : 0) + ((i & 0x20) ? 85 : 0);

  397.                 b = 127 + ((i & 4) ? 43 : 0) + ((i & 0x40) ? 85 : 0);

  398.                 a = 255;

  399.                 break;

  400.             case 0x88:

  401.                 r = ((i & 1) ? 43 : 0) + ((i & 0x10) ? 85 : 0);

  402.                 g = ((i & 2) ? 43 : 0) + ((i & 0x20) ? 85 : 0);

  403.                 b = ((i & 4) ? 43 : 0) + ((i & 0x40) ? 85 : 0);

  404.                 a = 255;

  405.                 break;

  406.             }

  407.         }

  408.         default_clut.clut256[i] = RGBA(r, g, b, a);

  409.     }

  410. 

  411.     return 0;

  412. }

  413. 

  414. static int dvbsub_close_decoder(AVCodecContext *avctx)

  415. {

  416.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  417.     DVBSubRegionDisplay *display;

  418. 

  419.     delete_state(ctx);

  420. 

  421.     while (ctx->display_list) {

  422.         display = ctx->display_list;

  423.         ctx->display_list = display->next;

  424. 

  425.         av_free(display);

  426.     }

  427. 

  428.     return 0;

  429. }

  430. 

  431. static int dvbsub_read_2bit_string(uint8_t *destbuf, int dbuf_len,

  432.                                    const uint8_t **srcbuf, int buf_size,

  433.                                    int non_mod, uint8_t *map_table)

  434. {

  435.     GetBitContext gb;

  436. 

  437.     int bits;

  438.     int run_length;

  439.     int pixels_read = 0;

  440. 

  441.     init_get_bits(&gb, *srcbuf, buf_size << 8);

  442. 

  443.     while (get_bits_count(&gb) < (buf_size << 8) && pixels_read < dbuf_len) {

  444.         bits = get_bits(&gb, 2);

  445. 

  446.         if (bits) {

  447.             if (non_mod != 1 || bits != 1) {

  448.                 if (map_table)

  449.                     *destbuf++ = map_table[bits];

  450.                 else

  451.                     *destbuf++ = bits;

  452.             }

  453.             pixels_read++;

  454.         } else {

  455.             bits = get_bits1(&gb);

  456.             if (bits == 1) {

  457.                 run_length = get_bits(&gb, 3) + 3;

  458.                 bits = get_bits(&gb, 2);

  459. 

  460.                 if (non_mod == 1 && bits == 1)

  461.                     pixels_read += run_length;

  462.                 else {

  463.                     if (map_table)

  464.                         bits = map_table[bits];

  465.                     while (run_length-- > 0 && pixels_read < dbuf_len) {

  466.                         *destbuf++ = bits;

  467.                         pixels_read++;

  468.                     }

  469.                 }

  470.             } else {

  471.                 bits = get_bits1(&gb);

  472.                 if (bits == 0) {

  473.                     bits = get_bits(&gb, 2);

  474.                     if (bits == 2) {

  475.                         run_length = get_bits(&gb, 4) + 12;

  476.                         bits = get_bits(&gb, 2);

  477. 

  478.                         if (non_mod == 1 && bits == 1)

  479.                             pixels_read += run_length;

  480.                         else {

  481.                             if (map_table)

  482.                                 bits = map_table[bits];

  483.                             while (run_length-- > 0 && pixels_read < dbuf_len) {

  484.                                 *destbuf++ = bits;

  485.                                 pixels_read++;

  486.                             }

  487.                         }

  488.                     } else if (bits == 3) {

  489.                         run_length = get_bits(&gb, 8) + 29;

  490.                         bits = get_bits(&gb, 2);

  491. 

  492.                         if (non_mod == 1 && bits == 1)

  493.                             pixels_read += run_length;

  494.                         else {

  495.                             if (map_table)

  496.                                 bits = map_table[bits];

  497.                             while (run_length-- > 0 && pixels_read < dbuf_len) {

  498.                                 *destbuf++ = bits;

  499.                                 pixels_read++;

  500.                             }

  501.                         }

  502.                     } else if (bits == 1) {

  503.                         pixels_read += 2;

  504.                         if (map_table)

  505.                             bits = map_table[0];

  506.                         else

  507.                             bits = 0;

  508.                         if (pixels_read <= dbuf_len) {

  509.                             *destbuf++ = bits;

  510.                             *destbuf++ = bits;

  511.                         }

  512.                     } else {

  513.                         (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;

  514.                         return pixels_read;

  515.                     }

  516.                 } else {

  517.                     if (map_table)

  518.                         bits = map_table[0];

  519.                     else

  520.                         bits = 0;

  521.                     *destbuf++ = bits;

  522.                     pixels_read++;

  523.                 }

  524.             }

  525.         }

  526.     }

  527. 

  528.     if (get_bits(&gb, 6))

  529.         av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");

  530. 

  531.     (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;

  532. 

  533.     return pixels_read;

  534. }

  535. 

  536. static int dvbsub_read_4bit_string(uint8_t *destbuf, int dbuf_len,

  537.                                    const uint8_t **srcbuf, int buf_size,

  538.                                    int non_mod, uint8_t *map_table)

  539. {

  540.     GetBitContext gb;

  541. 

  542.     int bits;

  543.     int run_length;

  544.     int pixels_read = 0;

  545. 

  546.     init_get_bits(&gb, *srcbuf, buf_size << 8);

  547. 

  548.     while (get_bits_count(&gb) < (buf_size << 8) && pixels_read < dbuf_len) {

  549.         bits = get_bits(&gb, 4);

  550. 

  551.         if (bits) {

  552.             if (non_mod != 1 || bits != 1) {

  553.                 if (map_table)

  554.                     *destbuf++ = map_table[bits];

  555.                 else

  556.                     *destbuf++ = bits;

  557.             }

  558.             pixels_read++;

  559.         } else {

  560.             bits = get_bits1(&gb);

  561.             if (bits == 0) {

  562.                 run_length = get_bits(&gb, 3);

  563. 

  564.                 if (run_length == 0) {

  565.                     (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;

  566.                     return pixels_read;

  567.                 }

  568. 

  569.                 run_length += 2;

  570. 

  571.                 if (map_table)

  572.                     bits = map_table[0];

  573.                 else

  574.                     bits = 0;

  575. 

  576.                 while (run_length-- > 0 && pixels_read < dbuf_len) {

  577.                     *destbuf++ = bits;

  578.                     pixels_read++;

  579.                 }

  580.             } else {

  581.                 bits = get_bits1(&gb);

  582.                 if (bits == 0) {

  583.                     run_length = get_bits(&gb, 2) + 4;

  584.                     bits = get_bits(&gb, 4);

  585. 

  586.                     if (non_mod == 1 && bits == 1)

  587.                         pixels_read += run_length;

  588.                     else {

  589.                         if (map_table)

  590.                             bits = map_table[bits];

  591.                         while (run_length-- > 0 && pixels_read < dbuf_len) {

  592.                             *destbuf++ = bits;

  593.                             pixels_read++;

  594.                         }

  595.                     }

  596.                 } else {

  597.                     bits = get_bits(&gb, 2);

  598.                     if (bits == 2) {

  599.                         run_length = get_bits(&gb, 4) + 9;

  600.                         bits = get_bits(&gb, 4);

  601. 

  602.                         if (non_mod == 1 && bits == 1)

  603.                             pixels_read += run_length;

  604.                         else {

  605.                             if (map_table)

  606.                                 bits = map_table[bits];

  607.                             while (run_length-- > 0 && pixels_read < dbuf_len) {

  608.                                 *destbuf++ = bits;

  609.                                 pixels_read++;

  610.                             }

  611.                         }

  612.                     } else if (bits == 3) {

  613.                         run_length = get_bits(&gb, 8) + 25;

  614.                         bits = get_bits(&gb, 4);

  615. 

  616.                         if (non_mod == 1 && bits == 1)

  617.                             pixels_read += run_length;

  618.                         else {

  619.                             if (map_table)

  620.                                 bits = map_table[bits];

  621.                             while (run_length-- > 0 && pixels_read < dbuf_len) {

  622.                                 *destbuf++ = bits;

  623.                                 pixels_read++;

  624.                             }

  625.                         }

  626.                     } else if (bits == 1) {

  627.                         pixels_read += 2;

  628.                         if (map_table)

  629.                             bits = map_table[0];

  630.                         else

  631.                             bits = 0;

  632.                         if (pixels_read <= dbuf_len) {

  633.                             *destbuf++ = bits;

  634.                             *destbuf++ = bits;

  635.                         }

  636.                     } else {

  637.                         if (map_table)

  638.                             bits = map_table[0];

  639.                         else

  640.                             bits = 0;

  641.                         *destbuf++ = bits;

  642.                         pixels_read ++;

  643.                     }

  644.                 }

  645.             }

  646.         }

  647.     }

  648. 

  649.     if (get_bits(&gb, 8))

  650.         av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");

  651. 

  652.     (*srcbuf) += (get_bits_count(&gb) + 7) >> 3;

  653. 

  654.     return pixels_read;

  655. }

  656. 

  657. static int dvbsub_read_8bit_string(uint8_t *destbuf, int dbuf_len,

  658.                                     const uint8_t **srcbuf, int buf_size,

  659.                                     int non_mod, uint8_t *map_table)

  660. {

  661.     const uint8_t *sbuf_end = (*srcbuf) + buf_size;

  662.     int bits;

  663.     int run_length;

  664.     int pixels_read = 0;

  665. 

  666.     while (*srcbuf < sbuf_end && pixels_read < dbuf_len) {

  667.         bits = *(*srcbuf)++;

  668. 

  669.         if (bits) {

  670.             if (non_mod != 1 || bits != 1) {

  671.                 if (map_table)

  672.                     *destbuf++ = map_table[bits];

  673.                 else

  674.                     *destbuf++ = bits;

  675.             }

  676.             pixels_read++;

  677.         } else {

  678.             bits = *(*srcbuf)++;

  679.             run_length = bits & 0x7f;

  680.             if ((bits & 0x80) == 0) {

  681.                 if (run_length == 0) {

  682.                     return pixels_read;

  683.                 }

  684. 

  685.                 if (map_table)

  686.                     bits = map_table[0];

  687.                 else

  688.                     bits = 0;

  689.                 while (run_length-- > 0 && pixels_read < dbuf_len) {

  690.                     *destbuf++ = bits;

  691.                     pixels_read++;

  692.                 }

  693.             } else {

  694.                 bits = *(*srcbuf)++;

  695. 

  696.                 if (non_mod == 1 && bits == 1)

  697.                     pixels_read += run_length;

  698.                 if (map_table)

  699.                     bits = map_table[bits];

  700.                 else while (run_length-- > 0 && pixels_read < dbuf_len) {

  701.                     *destbuf++ = bits;

  702.                     pixels_read++;

  703.                 }

  704.             }

  705.         }

  706.     }

  707. 

  708.     if (*(*srcbuf)++)

  709.         av_log(0, AV_LOG_ERROR, "DVBSub error: line overflow\n");

  710. 

  711.     return pixels_read;

  712. }

  713. 

  714. 

  715. 

  716. static void dvbsub_parse_pixel_data_block(AVCodecContext *avctx, DVBSubObjectDisplay *display,

  717.                                           const uint8_t *buf, int buf_size, int top_bottom, int non_mod)

  718. {

  719.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  720. 

  721.     DVBSubRegion *region = get_region(ctx, display->region_id);

  722.     const uint8_t *buf_end = buf + buf_size;

  723.     uint8_t *pbuf;

  724.     int x_pos, y_pos;

  725.     int i;

  726. 

  727.     uint8_t map2to4[] = { 0x0,  0x7,  0x8,  0xf};

  728.     uint8_t map2to8[] = {0x00, 0x77, 0x88, 0xff};

  729.     uint8_t map4to8[] = {0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,

  730.                          0x88, 0x99, 0xaa, 0xbb, 0xcc, 0xdd, 0xee, 0xff};

  731.     uint8_t *map_table;

  732. 

  733. #ifdef DEBUG

  734.     av_log(avctx, AV_LOG_INFO, "DVB pixel block size %d, %s field:\n", buf_size,

  735.                 top_bottom ? "bottom" : "top");

  736. #endif

  737. 

  738. #ifdef DEBUG_PACKET_CONTENTS

  739.     for (i = 0; i < buf_size; i++) {

  740.         if (i % 16 == 0)

  741.             av_log(avctx, AV_LOG_INFO, "0x%08p: ", buf+i);

  742. 

  743.         av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);

  744.         if (i % 16 == 15)

  745.             av_log(avctx, AV_LOG_INFO, "\n");

  746.     }

  747. 

  748.     if (i % 16)

  749.         av_log(avctx, AV_LOG_INFO, "\n");

  750. 

  751. #endif

  752. 

  753.     if (region == 0)

  754.         return;

  755. 

  756.     pbuf = region->pbuf;

  757. 

  758.     x_pos = display->x_pos;

  759.     y_pos = display->y_pos;

  760. 

  761.     if ((y_pos & 1) != top_bottom)

  762.         y_pos++;

  763. 

  764.     while (buf < buf_end) {

  765.         if (x_pos > region->width || y_pos > region->height) {

  766.             av_log(avctx, AV_LOG_ERROR, "Invalid object location!\n");

  767.             return;

  768.         }

  769. 

  770.         switch (*buf++) {

  771.         case 0x10:

  772.             if (region->depth == 8)

  773.                 map_table = map2to8;

  774.             else if (region->depth == 4)

  775.                 map_table = map2to4;

  776.             else

  777.                 map_table = NULL;

  778. 

  779.             x_pos += dvbsub_read_2bit_string(pbuf + (y_pos * region->width) + x_pos,

  780.                                                 region->width - x_pos, &buf, buf_size,

  781.                                                 non_mod, map_table);

  782.             break;

  783.         case 0x11:

  784.             if (region->depth < 4) {

  785.                 av_log(avctx, AV_LOG_ERROR, "4-bit pixel string in %d-bit region!\n", region->depth);

  786.                 return;

  787.             }

  788. 

  789.             if (region->depth == 8)

  790.                 map_table = map4to8;

  791.             else

  792.                 map_table = NULL;

  793. 

  794.             x_pos += dvbsub_read_4bit_string(pbuf + (y_pos * region->width) + x_pos,

  795.                                                 region->width - x_pos, &buf, buf_size,

  796.                                                 non_mod, map_table);

  797.             break;

  798.         case 0x12:

  799.             if (region->depth < 8) {

  800.                 av_log(avctx, AV_LOG_ERROR, "8-bit pixel string in %d-bit region!\n", region->depth);

  801.                 return;

  802.             }

  803. 

  804.             x_pos += dvbsub_read_8bit_string(pbuf + (y_pos * region->width) + x_pos,

  805.                                                 region->width - x_pos, &buf, buf_size,

  806.                                                 non_mod, NULL);

  807.             break;

  808. 

  809.         case 0x20:

  810.             map2to4[0] = (*buf) >> 4;

  811.             map2to4[1] = (*buf++) & 0xf;

  812.             map2to4[2] = (*buf) >> 4;

  813.             map2to4[3] = (*buf++) & 0xf;

  814.             break;

  815.         case 0x21:

  816.             for (i = 0; i < 4; i++)

  817.                 map2to8[i] = *buf++;

  818.             break;

  819.         case 0x22:

  820.             for (i = 0; i < 16; i++)

  821.                 map4to8[i] = *buf++;

  822.             break;

  823. 

  824.         case 0xf0:

  825.             x_pos = display->x_pos;

  826.             y_pos += 2;

  827.             break;

  828.         default:

  829.             av_log(avctx, AV_LOG_INFO, "Unknown/unsupported pixel block 0x%x\n", *(buf-1));

  830.         }

  831.     }

  832. 

  833. }

  834. 

  835. static void dvbsub_parse_object_segment(AVCodecContext *avctx,

  836.                                         const uint8_t *buf, int buf_size)

  837. {

  838.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  839. 

  840.     const uint8_t *buf_end = buf + buf_size;

  841.     const uint8_t *block;

  842.     int object_id;

  843.     DVBSubObject *object;

  844.     DVBSubObjectDisplay *display;

  845.     int top_field_len, bottom_field_len;

  846. 

  847.     int coding_method, non_modifying_color;

  848. 

  849.     object_id = AV_RB16(buf);

  850.     buf += 2;

  851. 

  852.     object = get_object(ctx, object_id);

  853. 

  854.     if (!object)

  855.         return;

  856. 

  857.     coding_method = ((*buf) >> 2) & 3;

  858.     non_modifying_color = ((*buf++) >> 1) & 1;

  859. 

  860.     if (coding_method == 0) {

  861.         top_field_len = AV_RB16(buf);

  862.         buf += 2;

  863.         bottom_field_len = AV_RB16(buf);

  864.         buf += 2;

  865. 

  866.         if (buf + top_field_len + bottom_field_len > buf_end) {

  867.             av_log(avctx, AV_LOG_ERROR, "Field data size too large\n");

  868.             return;

  869.         }

  870. 

  871.         for (display = object->display_list; display; display = display->object_list_next) {

  872.             block = buf;

  873. 

  874.             dvbsub_parse_pixel_data_block(avctx, display, block, top_field_len, 0,

  875.                                             non_modifying_color);

  876. 

  877.             if (bottom_field_len > 0)

  878.                 block = buf + top_field_len;

  879.             else

  880.                 bottom_field_len = top_field_len;

  881. 

  882.             dvbsub_parse_pixel_data_block(avctx, display, block, bottom_field_len, 1,

  883.                                             non_modifying_color);

  884.         }

  885. 

  886. /*  } else if (coding_method == 1) {*/

  887. 

  888.     } else {

  889.         av_log(avctx, AV_LOG_ERROR, "Unknown object coding %d\n", coding_method);

  890.     }

  891. 

  892. }

  893. 

  894. static void dvbsub_parse_clut_segment(AVCodecContext *avctx,

  895.                                         const uint8_t *buf, int buf_size)

  896. {

  897.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  898. 

  899.     const uint8_t *buf_end = buf + buf_size;

  900.     int clut_id;

  901.     DVBSubCLUT *clut;

  902.     int entry_id, depth , full_range;

  903.     int y, cr, cb, alpha;

  904.     int r, g, b, r_add, g_add, b_add;

  905. 

  906. #ifdef DEBUG_PACKET_CONTENTS

  907.     int i;

  908. 

  909.     av_log(avctx, AV_LOG_INFO, "DVB clut packet:\n");

  910. 

  911.     for (i=0; i < buf_size; i++) {

  912.         av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);

  913.         if (i % 16 == 15)

  914.             av_log(avctx, AV_LOG_INFO, "\n");

  915.     }

  916. 

  917.     if (i % 16)

  918.         av_log(avctx, AV_LOG_INFO, "\n");

  919. 

  920. #endif

  921. 

  922.     clut_id = *buf++;

  923.     buf += 1;

  924. 

  925.     clut = get_clut(ctx, clut_id);

  926. 

  927.     if (!clut) {

  928.         clut = av_malloc(sizeof(DVBSubCLUT));

  929. 

  930.         memcpy(clut, &default_clut, sizeof(DVBSubCLUT));

  931. 

  932.         clut->id = clut_id;

  933. 

  934.         clut->next = ctx->clut_list;

  935.         ctx->clut_list = clut;

  936.     }

  937. 

  938.     while (buf + 4 < buf_end) {

  939.         entry_id = *buf++;

  940. 

  941.         depth = (*buf) & 0xe0;

  942. 

  943.         if (depth == 0) {

  944.             av_log(avctx, AV_LOG_ERROR, "Invalid clut depth 0x%x!\n", *buf);

  945.             return;

  946.         }

  947. 

  948.         full_range = (*buf++) & 1;

  949. 

  950.         if (full_range) {

  951.             y = *buf++;

  952.             cr = *buf++;

  953.             cb = *buf++;

  954.             alpha = *buf++;

  955.         } else {

  956.             y = buf[0] & 0xfc;

  957.             cr = (((buf[0] & 3) << 2) | ((buf[1] >> 6) & 3)) << 4;

  958.             cb = (buf[1] << 2) & 0xf0;

  959.             alpha = (buf[1] << 6) & 0xc0;

  960. 

  961.             buf += 2;

  962.         }

  963. 

  964.         if (y == 0)

  965.             alpha = 0xff;

  966. 

  967.         YUV_TO_RGB1_CCIR(cb, cr);

  968.         YUV_TO_RGB2_CCIR(r, g, b, y);

  969. 

  970. #ifdef DEBUG

  971.         av_log(avctx, AV_LOG_INFO, "clut %d := (%d,%d,%d,%d)\n", entry_id, r, g, b, alpha);

  972. #endif

  973. 

  974.         if (depth & 0x80)

  975.             clut->clut4[entry_id] = RGBA(r,g,b,255 - alpha);

  976.         if (depth & 0x40)

  977.             clut->clut16[entry_id] = RGBA(r,g,b,255 - alpha);

  978.         if (depth & 0x20)

  979.             clut->clut256[entry_id] = RGBA(r,g,b,255 - alpha);

  980.     }

  981. }

  982. 

  983. 

  984. static void dvbsub_parse_region_segment(AVCodecContext *avctx,

  985.                                         const uint8_t *buf, int buf_size)

  986. {

  987.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  988. 

  989.     const uint8_t *buf_end = buf + buf_size;

  990.     int region_id, object_id;

  991.     DVBSubRegion *region;

  992.     DVBSubObject *object;

  993.     DVBSubObjectDisplay *display;

  994.     int fill;

  995. 

  996.     if (buf_size < 10)

  997.         return;

  998. 

  999.     region_id = *buf++;

  1000. 

  1001.     region = get_region(ctx, region_id);

  1002. 

  1003.     if (!region) {

  1004.         region = av_mallocz(sizeof(DVBSubRegion));

  1005. 

  1006.         region->id = region_id;

  1007. 

  1008.         region->next = ctx->region_list;

  1009.         ctx->region_list = region;

  1010.     }

  1011. 

  1012.     fill = ((*buf++) >> 3) & 1;

  1013. 

  1014.     region->width = AV_RB16(buf);

  1015.     buf += 2;

  1016.     region->height = AV_RB16(buf);

  1017.     buf += 2;

  1018. 

  1019.     if (region->width * region->height != region->buf_size) {

  1020.         if (region->pbuf)

  1021.             av_free(region->pbuf);

  1022. 

  1023.         region->buf_size = region->width * region->height;

  1024. 

  1025.         region->pbuf = av_malloc(region->buf_size);

  1026. 

  1027.         fill = 1;

  1028.     }

  1029. 

  1030.     region->depth = 1 << (((*buf++) >> 2) & 7);

  1031.     if(region->depth<2 || region->depth>8){

  1032.         av_log(avctx, AV_LOG_ERROR, "region depth %d is invalid\n", region->depth);

  1033.         region->depth= 4;

  1034.     }

  1035.     region->clut = *buf++;

  1036. 

  1037.     if (region->depth == 8)

  1038.         region->bgcolor = *buf++;

  1039.     else {

  1040.         buf += 1;

  1041. 

  1042.         if (region->depth == 4)

  1043.             region->bgcolor = (((*buf++) >> 4) & 15);

  1044.         else

  1045.             region->bgcolor = (((*buf++) >> 2) & 3);

  1046.     }

  1047. 

  1048. #ifdef DEBUG

  1049.     av_log(avctx, AV_LOG_INFO, "Region %d, (%dx%d)\n", region_id, region->width, region->height);

  1050. #endif

  1051. 

  1052.     if (fill) {

  1053.         memset(region->pbuf, region->bgcolor, region->buf_size);

  1054. #ifdef DEBUG

  1055.         av_log(avctx, AV_LOG_INFO, "Fill region (%d)\n", region->bgcolor);

  1056. #endif

  1057.     }

  1058. 

  1059.     delete_region_display_list(ctx, region);

  1060. 

  1061.     while (buf + 5 < buf_end) {

  1062.         object_id = AV_RB16(buf);

  1063.         buf += 2;

  1064. 

  1065.         object = get_object(ctx, object_id);

  1066. 

  1067.         if (!object) {

  1068.             object = av_mallocz(sizeof(DVBSubObject));

  1069. 

  1070.             object->id = object_id;

  1071.             object->next = ctx->object_list;

  1072.             ctx->object_list = object;

  1073.         }

  1074. 

  1075.         object->type = (*buf) >> 6;

  1076. 

  1077.         display = av_mallocz(sizeof(DVBSubObjectDisplay));

  1078. 

  1079.         display->object_id = object_id;

  1080.         display->region_id = region_id;

  1081. 

  1082.         display->x_pos = AV_RB16(buf) & 0xfff;

  1083.         buf += 2;

  1084.         display->y_pos = AV_RB16(buf) & 0xfff;

  1085.         buf += 2;

  1086. 

  1087.         if ((object->type == 1 || object->type == 2) && buf+1 < buf_end) {

  1088.             display->fgcolor = *buf++;

  1089.             display->bgcolor = *buf++;

  1090.         }

  1091. 

  1092.         display->region_list_next = region->display_list;

  1093.         region->display_list = display;

  1094. 

  1095.         display->object_list_next = object->display_list;

  1096.         object->display_list = display;

  1097.     }

  1098. }

  1099. 

  1100. static void dvbsub_parse_page_segment(AVCodecContext *avctx,

  1101.                                         const uint8_t *buf, int buf_size)

  1102. {

  1103.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  1104.     DVBSubRegionDisplay *display;

  1105.     DVBSubRegionDisplay *tmp_display_list, **tmp_ptr;

  1106. 

  1107.     const uint8_t *buf_end = buf + buf_size;

  1108.     int region_id;

  1109.     int page_state;

  1110. 

  1111.     if (buf_size < 1)

  1112.         return;

  1113. 

  1114.     ctx->time_out = *buf++;

  1115.     page_state = ((*buf++) >> 2) & 3;

  1116. 

  1117. #ifdef DEBUG

  1118.     av_log(avctx, AV_LOG_INFO, "Page time out %ds, state %d\n", ctx->time_out, page_state);

  1119. #endif

  1120. 

  1121.     if (page_state == 2) {

  1122.         delete_state(ctx);

  1123.     }

  1124. 

  1125.     tmp_display_list = ctx->display_list;

  1126.     ctx->display_list = NULL;

  1127.     ctx->display_list_size = 0;

  1128. 

  1129.     while (buf + 5 < buf_end) {

  1130.         region_id = *buf++;

  1131.         buf += 1;

  1132. 

  1133.         display = tmp_display_list;

  1134.         tmp_ptr = &tmp_display_list;

  1135. 

  1136.         while (display && display->region_id != region_id) {

  1137.             tmp_ptr = &display->next;

  1138.             display = display->next;

  1139.         }

  1140. 

  1141.         if (!display)

  1142.             display = av_mallocz(sizeof(DVBSubRegionDisplay));

  1143. 

  1144.         display->region_id = region_id;

  1145. 

  1146.         display->x_pos = AV_RB16(buf);

  1147.         buf += 2;

  1148.         display->y_pos = AV_RB16(buf);

  1149.         buf += 2;

  1150. 

  1151.         *tmp_ptr = display->next;

  1152. 

  1153.         display->next = ctx->display_list;

  1154.         ctx->display_list = display;

  1155.         ctx->display_list_size++;

  1156. 

  1157. #ifdef DEBUG

  1158.         av_log(avctx, AV_LOG_INFO, "Region %d, (%d,%d)\n", region_id, display->x_pos, display->y_pos);

  1159. #endif

  1160.     }

  1161. 

  1162.     while (tmp_display_list) {

  1163.         display = tmp_display_list;

  1164. 

  1165.         tmp_display_list = display->next;

  1166. 

  1167.         av_free(display);

  1168.     }

  1169. 

  1170. }

  1171. 

  1172. 

  1173. #ifdef DEBUG_SAVE_IMAGES

  1174. static void save_display_set(DVBSubContext *ctx)

  1175. {

  1176.     DVBSubRegion *region;

  1177.     DVBSubRegionDisplay *display;

  1178.     DVBSubCLUT *clut;

  1179.     uint32_t *clut_table;

  1180.     int x_pos, y_pos, width, height;

  1181.     int x, y, y_off, x_off;

  1182.     uint32_t *pbuf;

  1183.     char filename[32];

  1184.     static int fileno_index = 0;

  1185. 

  1186.     x_pos = -1;

  1187.     y_pos = -1;

  1188.     width = 0;

  1189.     height = 0;

  1190. 

  1191.     for (display = ctx->display_list; display; display = display->next) {

  1192.         region = get_region(ctx, display->region_id);

  1193. 

  1194.         if (x_pos == -1) {

  1195.             x_pos = display->x_pos;

  1196.             y_pos = display->y_pos;

  1197.             width = region->width;

  1198.             height = region->height;

  1199.         } else {

  1200.             if (display->x_pos < x_pos) {

  1201.                 width += (x_pos - display->x_pos);

  1202.                 x_pos = display->x_pos;

  1203.             }

  1204. 

  1205.             if (display->y_pos < y_pos) {

  1206.                 height += (y_pos - display->y_pos);

  1207.                 y_pos = display->y_pos;

  1208.             }

  1209. 

  1210.             if (display->x_pos + region->width > x_pos + width) {

  1211.                 width = display->x_pos + region->width - x_pos;

  1212.             }

  1213. 

  1214.             if (display->y_pos + region->height > y_pos + height) {

  1215.                 height = display->y_pos + region->height - y_pos;

  1216.             }

  1217.         }

  1218.     }

  1219. 

  1220.     if (x_pos >= 0) {

  1221. 

  1222.         pbuf = av_malloc(width * height * 4);

  1223. 

  1224.         for (display = ctx->display_list; display; display = display->next) {

  1225.             region = get_region(ctx, display->region_id);

  1226. 

  1227.             x_off = display->x_pos - x_pos;

  1228.             y_off = display->y_pos - y_pos;

  1229. 

  1230.             clut = get_clut(ctx, region->clut);

  1231. 

  1232.             if (clut == 0)

  1233.                 clut = &default_clut;

  1234. 

  1235.             switch (region->depth) {

  1236.             case 2:

  1237.                 clut_table = clut->clut4;

  1238.                 break;

  1239.             case 8:

  1240.                 clut_table = clut->clut256;

  1241.                 break;

  1242.             case 4:

  1243.             default:

  1244.                 clut_table = clut->clut16;

  1245.                 break;

  1246.             }

  1247. 

  1248.             for (y = 0; y < region->height; y++) {

  1249.                 for (x = 0; x < region->width; x++) {

  1250.                     pbuf[((y + y_off) * width) + x_off + x] =

  1251.                         clut_table[region->pbuf[y * region->width + x]];

  1252.                 }

  1253.             }

  1254. 

  1255.         }

  1256. 

  1257.         snprintf(filename, sizeof(filename), "dvbs.%d", fileno_index);

  1258. 

  1259.         png_save2(filename, pbuf, width, height);

  1260. 

  1261.         av_free(pbuf);

  1262.     }

  1263. 

  1264.     fileno_index++;

  1265. }

  1266. #endif

  1267. 

  1268. static int dvbsub_display_end_segment(AVCodecContext *avctx, const uint8_t *buf,

  1269.                                         int buf_size, AVSubtitle *sub)

  1270. {

  1271.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  1272. 

  1273.     DVBSubRegion *region;

  1274.     DVBSubRegionDisplay *display;

  1275.     AVSubtitleRect *rect;

  1276.     DVBSubCLUT *clut;

  1277.     uint32_t *clut_table;

  1278.     int i;

  1279. 

  1280.     sub->rects = NULL;

  1281.     sub->start_display_time = 0;

  1282.     sub->end_display_time = ctx->time_out * 1000;

  1283.     sub->format = 0;

  1284. 

  1285.     sub->num_rects = ctx->display_list_size;

  1286. 

  1287.     if (sub->num_rects > 0)

  1288.         sub->rects = av_mallocz(sizeof(AVSubtitleRect) * sub->num_rects);

  1289. 

  1290.     i = 0;

  1291. 

  1292.     for (display = ctx->display_list; display; display = display->next) {

  1293.         region = get_region(ctx, display->region_id);

  1294.         rect = &sub->rects[i];

  1295. 

  1296.         if (!region)

  1297.             continue;

  1298. 

  1299.         rect->x = display->x_pos;

  1300.         rect->y = display->y_pos;

  1301.         rect->w = region->width;

  1302.         rect->h = region->height;

  1303.         rect->nb_colors = 16;

  1304.         rect->linesize = region->width;

  1305. 

  1306.         clut = get_clut(ctx, region->clut);

  1307. 

  1308.         if (!clut)

  1309.             clut = &default_clut;

  1310. 

  1311.         switch (region->depth) {

  1312.         case 2:

  1313.             clut_table = clut->clut4;

  1314.             break;

  1315.         case 8:

  1316.             clut_table = clut->clut256;

  1317.             break;

  1318.         case 4:

  1319.         default:

  1320.             clut_table = clut->clut16;

  1321.             break;

  1322.         }

  1323. 

  1324.         rect->rgba_palette = av_malloc((1 << region->depth) * sizeof(uint32_t));

  1325.         memcpy(rect->rgba_palette, clut_table, (1 << region->depth) * sizeof(uint32_t));

  1326. 

  1327.         rect->bitmap = av_malloc(region->buf_size);

  1328.         memcpy(rect->bitmap, region->pbuf, region->buf_size);

  1329. 

  1330.         i++;

  1331.     }

  1332. 

  1333.     sub->num_rects = i;

  1334. 

  1335. #ifdef DEBUG_SAVE_IMAGES

  1336.     save_display_set(ctx);

  1337. #endif

  1338. 

  1339.     return 1;

  1340. }

  1341. 

  1342. static int dvbsub_decode(AVCodecContext *avctx,

  1343.                          void *data, int *data_size,

  1344.                          const uint8_t *buf, int buf_size)

  1345. {

  1346.     DVBSubContext *ctx = (DVBSubContext*) avctx->priv_data;

  1347.     AVSubtitle *sub = (AVSubtitle*) data;

  1348.     const uint8_t *p, *p_end;

  1349.     int segment_type;

  1350.     int page_id;

  1351.     int segment_length;

  1352. 

  1353. #ifdef DEBUG_PACKET_CONTENTS

  1354.     int i;

  1355. 

  1356.     av_log(avctx, AV_LOG_INFO, "DVB sub packet:\n");

  1357. 

  1358.     for (i=0; i < buf_size; i++) {

  1359.         av_log(avctx, AV_LOG_INFO, "%02x ", buf[i]);

  1360.         if (i % 16 == 15)

  1361.             av_log(avctx, AV_LOG_INFO, "\n");

  1362.     }

  1363. 

  1364.     if (i % 16)

  1365.         av_log(avctx, AV_LOG_INFO, "\n");

  1366. 

  1367. #endif

  1368. 

  1369.     if (buf_size <= 2)

  1370.         return -1;

  1371. 

  1372.     p = buf;

  1373.     p_end = buf + buf_size;

  1374. 

  1375.     while (p < p_end && *p == 0x0f) {

  1376.         p += 1;

  1377.         segment_type = *p++;

  1378.         page_id = AV_RB16(p);

  1379.         p += 2;

  1380.         segment_length = AV_RB16(p);

  1381.         p += 2;

  1382. 

  1383.         if (page_id == ctx->composition_id || page_id == ctx->ancillary_id) {

  1384.             switch (segment_type) {

  1385.             case DVBSUB_PAGE_SEGMENT:

  1386.                 dvbsub_parse_page_segment(avctx, p, segment_length);

  1387.                 break;

  1388.             case DVBSUB_REGION_SEGMENT:

  1389.                 dvbsub_parse_region_segment(avctx, p, segment_length);

  1390.                 break;

  1391.             case DVBSUB_CLUT_SEGMENT:

  1392.                 dvbsub_parse_clut_segment(avctx, p, segment_length);

  1393.                 break;

  1394.             case DVBSUB_OBJECT_SEGMENT:

  1395.                 dvbsub_parse_object_segment(avctx, p, segment_length);

  1396.                 break;

  1397.             case DVBSUB_DISPLAY_SEGMENT:

  1398.                 *data_size = dvbsub_display_end_segment(avctx, p, segment_length, sub);

  1399.                 break;

  1400.             default:

  1401. #ifdef DEBUG

  1402.                 av_log(avctx, AV_LOG_INFO, "Subtitling segment type 0x%x, page id %d, length %d\n",

  1403.                         segment_type, page_id, segment_length);

  1404. #endif

  1405.                 break;

  1406.             }

  1407.         }

  1408. 

  1409.         p += segment_length;

  1410.     }

  1411. 

  1412.     if (p != p_end) {

  1413. #ifdef DEBUG

  1414.         av_log(avctx, AV_LOG_INFO, "Junk at end of packet\n");

  1415. #endif

  1416.         return -1;

  1417.     }

  1418. 

  1419.     return buf_size;

  1420. }

  1421. 

  1422. 

  1423. AVCodec dvbsub_decoder = {

  1424.     "dvbsub",

  1425.     CODEC_TYPE_SUBTITLE,

  1426.     CODEC_ID_DVB_SUBTITLE,

  1427.     sizeof(DVBSubContext),

  1428.     dvbsub_init_decoder,

  1429.     NULL,

  1430.     dvbsub_close_decoder,

  1431.     dvbsub_decode,

  1432. };