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FFmpeg/libavcodec/tiff.c

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  1. /*

  2.  * Copyright (c) 2006 Konstantin Shishkov

  3.  *

  4.  * This file is part of FFmpeg.

  5.  *

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

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

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

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

  10.  *

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

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

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

  14.  * Lesser General Public License for more details.

  15.  *

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

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

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

  19.  */

  20. 

  21. /**

  22.  * @file

  23.  * TIFF image decoder

  24.  * @author Konstantin Shishkov

  25.  */

  26. 

  27. #include "avcodec.h"

  28. #if CONFIG_ZLIB

  29. #include <zlib.h>

  30. #endif

  31. #include "lzw.h"

  32. #include "tiff.h"

  33. #include "faxcompr.h"

  34. #include "libavutil/common.h"

  35. #include "libavutil/intreadwrite.h"

  36. #include "libavutil/imgutils.h"

  37. 

  38. typedef struct TiffContext {

  39.     AVCodecContext *avctx;

  40.     AVFrame picture;

  41. 

  42.     int width, height;

  43.     unsigned int bpp, bppcount;

  44.     uint32_t palette[256];

  45.     int palette_is_set;

  46.     int le;

  47.     enum TiffCompr compr;

  48.     int invert;

  49.     int fax_opts;

  50.     int predictor;

  51.     int fill_order;

  52. 

  53.     int strips, rps, sstype;

  54.     int sot;

  55.     const uint8_t* stripdata;

  56.     const uint8_t* stripsizes;

  57.     int stripsize, stripoff;

  58.     LZWState *lzw;

  59. } TiffContext;

  60. 

  61. static unsigned tget_short(const uint8_t **p, int le) {

  62.     unsigned v = le ? AV_RL16(*p) : AV_RB16(*p);

  63.     *p += 2;

  64.     return v;

  65. }

  66. 

  67. static unsigned tget_long(const uint8_t **p, int le) {

  68.     unsigned v = le ? AV_RL32(*p) : AV_RB32(*p);

  69.     *p += 4;

  70.     return v;

  71. }

  72. 

  73. static unsigned tget(const uint8_t **p, int type, int le) {

  74.     switch(type){

  75.     case TIFF_BYTE : return *(*p)++;

  76.     case TIFF_SHORT: return tget_short(p, le);

  77.     case TIFF_LONG : return tget_long (p, le);

  78.     default        : return UINT_MAX;

  79.     }

  80. }

  81. 

  82. #if CONFIG_ZLIB

  83. static int tiff_uncompress(uint8_t *dst, unsigned long *len, const uint8_t *src, int size)

  84. {

  85.     z_stream zstream = { 0 };

  86.     int zret;

  87. 

  88.     zstream.next_in = src;

  89.     zstream.avail_in = size;

  90.     zstream.next_out = dst;

  91.     zstream.avail_out = *len;

  92.     zret = inflateInit(&zstream);

  93.     if (zret != Z_OK) {

  94.         av_log(NULL, AV_LOG_ERROR, "Inflate init error: %d\n", zret);

  95.         return zret;

  96.     }

  97.     zret = inflate(&zstream, Z_SYNC_FLUSH);

  98.     inflateEnd(&zstream);

  99.     *len = zstream.total_out;

  100.     return zret == Z_STREAM_END ? Z_OK : zret;

  101. }

  102. #endif

  103. 

  104. static void av_always_inline horizontal_fill(unsigned int bpp, uint8_t* dst,

  105.                                              int usePtr, const uint8_t *src,

  106.                                              uint8_t c, int width, int offset)

  107. {

  108.     switch (bpp) {

  109.     case 1:

  110.         while (--width >= 0) {

  111.             dst[(width+offset)*8+7] = (usePtr ? src[width] : c)      & 0x1;

  112.             dst[(width+offset)*8+6] = (usePtr ? src[width] : c) >> 1 & 0x1;

  113.             dst[(width+offset)*8+5] = (usePtr ? src[width] : c) >> 2 & 0x1;

  114.             dst[(width+offset)*8+4] = (usePtr ? src[width] : c) >> 3 & 0x1;

  115.             dst[(width+offset)*8+3] = (usePtr ? src[width] : c) >> 4 & 0x1;

  116.             dst[(width+offset)*8+2] = (usePtr ? src[width] : c) >> 5 & 0x1;

  117.             dst[(width+offset)*8+1] = (usePtr ? src[width] : c) >> 6 & 0x1;

  118.             dst[(width+offset)*8+0] = (usePtr ? src[width] : c) >> 7;

  119.         }

  120.         break;

  121.     case 2:

  122.         while (--width >= 0) {

  123.             dst[(width+offset)*4+3] = (usePtr ? src[width] : c) & 0x3;

  124.             dst[(width+offset)*4+2] = (usePtr ? src[width] : c) >> 2 & 0x3;

  125.             dst[(width+offset)*4+1] = (usePtr ? src[width] : c) >> 4 & 0x3;

  126.             dst[(width+offset)*4+0] = (usePtr ? src[width] : c) >> 6;

  127.         }

  128.         break;

  129.     case 4:

  130.         while (--width >= 0) {

  131.             dst[(width+offset)*2+1] = (usePtr ? src[width] : c) & 0xF;

  132.             dst[(width+offset)*2+0] = (usePtr ? src[width] : c) >> 4;

  133.         }

  134.         break;

  135.     default:

  136.         if (usePtr) {

  137.             memcpy(dst + offset, src, width);

  138.         } else {

  139.             memset(dst + offset, c, width);

  140.         }

  141.     }

  142. }

  143. 

  144. static int tiff_unpack_strip(TiffContext *s, uint8_t* dst, int stride, const uint8_t *src, int size, int lines){

  145.     int c, line, pixels, code;

  146.     const uint8_t *ssrc = src;

  147.     int width = ((s->width * s->bpp) + 7) >> 3;

  148. 

  149.     if (size <= 0)

  150.         return AVERROR_INVALIDDATA;

  151. 

  152. #if CONFIG_ZLIB

  153.     if(s->compr == TIFF_DEFLATE || s->compr == TIFF_ADOBE_DEFLATE){

  154.         uint8_t *zbuf; unsigned long outlen;

  155.         int ret;

  156.         outlen = width * lines;

  157.         zbuf = av_malloc(outlen);

  158.         if (!zbuf)

  159.             return AVERROR(ENOMEM);

  160.         ret = tiff_uncompress(zbuf, &outlen, src, size);

  161.         if(ret != Z_OK){

  162.             av_log(s->avctx, AV_LOG_ERROR, "Uncompressing failed (%lu of %lu) with error %d\n", outlen, (unsigned long)width * lines, ret);

  163.             av_free(zbuf);

  164.             return -1;

  165.         }

  166.         src = zbuf;

  167.         for(line = 0; line < lines; line++){

  168.             if(s->bpp < 8 && s->avctx->pix_fmt == PIX_FMT_PAL8){

  169.                 horizontal_fill(s->bpp, dst, 1, src, 0, width, 0);

  170.             }else{

  171.                 memcpy(dst, src, width);

  172.             }

  173.             dst += stride;

  174.             src += width;

  175.         }

  176.         av_free(zbuf);

  177.         return 0;

  178.     }

  179. #endif

  180.     if(s->compr == TIFF_LZW){

  181.         if(ff_lzw_decode_init(s->lzw, 8, src, size, FF_LZW_TIFF) < 0){

  182.             av_log(s->avctx, AV_LOG_ERROR, "Error initializing LZW decoder\n");

  183.             return -1;

  184.         }

  185.     }

  186.     if(s->compr == TIFF_CCITT_RLE || s->compr == TIFF_G3 || s->compr == TIFF_G4){

  187.         int i, ret = 0;

  188.         uint8_t *src2 = av_malloc((unsigned)size + FF_INPUT_BUFFER_PADDING_SIZE);

  189. 

  190.         if (!src2) {

  191.             av_log(s->avctx, AV_LOG_ERROR, "Error allocating temporary buffer\n");

  192.             return AVERROR(ENOMEM);

  193.         }

  194.         if(s->fax_opts & 2){

  195.             av_log(s->avctx, AV_LOG_ERROR, "Uncompressed fax mode is not supported (yet)\n");

  196.             av_free(src2);

  197.             return -1;

  198.         }

  199.         if(!s->fill_order){

  200.             memcpy(src2, src, size);

  201.         }else{

  202.             for(i = 0; i < size; i++)

  203.                 src2[i] = av_reverse[src[i]];

  204.         }

  205.         memset(src2+size, 0, FF_INPUT_BUFFER_PADDING_SIZE);

  206.         switch(s->compr){

  207.         case TIFF_CCITT_RLE:

  208.         case TIFF_G3:

  209.         case TIFF_G4:

  210.             ret = ff_ccitt_unpack(s->avctx, src2, size, dst, lines, stride, s->compr, s->fax_opts);

  211.             break;

  212.         }

  213.         if (s->bpp < 8 && s->avctx->pix_fmt == PIX_FMT_PAL8)

  214.             for (line = 0; line < lines; line++) {

  215.                 horizontal_fill(s->bpp, dst, 1, dst, 0, width, 0);

  216.                 dst += stride;

  217.             }

  218.         av_free(src2);

  219.         return ret;

  220.     }

  221.     for(line = 0; line < lines; line++){

  222.         if(src - ssrc > size){

  223.             av_log(s->avctx, AV_LOG_ERROR, "Source data overread\n");

  224.             return -1;

  225.         }

  226.         switch(s->compr){

  227.         case TIFF_RAW:

  228.             if (ssrc + size - src < width)

  229.                 return AVERROR_INVALIDDATA;

  230.             if (!s->fill_order) {

  231.                 horizontal_fill(s->bpp * (s->avctx->pix_fmt == PIX_FMT_PAL8),

  232.                                 dst, 1, src, 0, width, 0);

  233.             } else {

  234.                 int i;

  235.                 for (i = 0; i < width; i++)

  236.                     dst[i] = av_reverse[src[i]];

  237.             }

  238.             src += width;

  239.             break;

  240.         case TIFF_PACKBITS:

  241.             for(pixels = 0; pixels < width;){

  242.                 code = (int8_t)*src++;

  243.                 if(code >= 0){

  244.                     code++;

  245.                     if(pixels + code > width){

  246.                         av_log(s->avctx, AV_LOG_ERROR, "Copy went out of bounds\n");

  247.                         return -1;

  248.                     }

  249.                     horizontal_fill(s->bpp * (s->avctx->pix_fmt == PIX_FMT_PAL8),

  250.                                     dst, 1, src, 0, code, pixels);

  251.                     src += code;

  252.                     pixels += code;

  253.                 }else if(code != -128){ // -127..-1

  254.                     code = (-code) + 1;

  255.                     if(pixels + code > width){

  256.                         av_log(s->avctx, AV_LOG_ERROR, "Run went out of bounds\n");

  257.                         return -1;

  258.                     }

  259.                     c = *src++;

  260.                     horizontal_fill(s->bpp * (s->avctx->pix_fmt == PIX_FMT_PAL8),

  261.                                     dst, 0, NULL, c, code, pixels);

  262.                     pixels += code;

  263.                 }

  264.             }

  265.             break;

  266.         case TIFF_LZW:

  267.             pixels = ff_lzw_decode(s->lzw, dst, width);

  268.             if(pixels < width){

  269.                 av_log(s->avctx, AV_LOG_ERROR, "Decoded only %i bytes of %i\n", pixels, width);

  270.                 return -1;

  271.             }

  272.             if (s->bpp < 8 && s->avctx->pix_fmt == PIX_FMT_PAL8)

  273.                 horizontal_fill(s->bpp, dst, 1, dst, 0, width, 0);

  274.             break;

  275.         }

  276.         dst += stride;

  277.     }

  278.     return 0;

  279. }

  280. 

  281. static int init_image(TiffContext *s)

  282. {

  283.     int i, ret;

  284.     uint32_t *pal;

  285. 

  286.     switch (s->bpp * 10 + s->bppcount) {

  287.     case 11:

  288.         if (!s->palette_is_set) {

  289.             s->avctx->pix_fmt = PIX_FMT_MONOBLACK;

  290.             break;

  291.         }

  292.     case 21:

  293.     case 41:

  294.     case 81:

  295.         s->avctx->pix_fmt = PIX_FMT_PAL8;

  296.         break;

  297.     case 243:

  298.         s->avctx->pix_fmt = PIX_FMT_RGB24;

  299.         break;

  300.     case 161:

  301.         s->avctx->pix_fmt = PIX_FMT_GRAY16BE;

  302.         break;

  303.     case 162:

  304.         s->avctx->pix_fmt = PIX_FMT_GRAY8A;

  305.         break;

  306.     case 324:

  307.         s->avctx->pix_fmt = PIX_FMT_RGBA;

  308.         break;

  309.     case 483:

  310.         s->avctx->pix_fmt = s->le ? PIX_FMT_RGB48LE : PIX_FMT_RGB48BE;

  311.         break;

  312.     case 644:

  313.         s->avctx->pix_fmt = s->le ? PIX_FMT_RGBA64LE : PIX_FMT_RGBA64BE;

  314.         break;

  315.     default:

  316.         av_log(s->avctx, AV_LOG_ERROR,

  317.                "This format is not supported (bpp=%d, bppcount=%d)\n",

  318.                s->bpp, s->bppcount);

  319.         return AVERROR_INVALIDDATA;

  320.     }

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

  322.         if ((ret = av_image_check_size(s->width, s->height, 0, s->avctx)) < 0)

  323.             return ret;

  324.         avcodec_set_dimensions(s->avctx, s->width, s->height);

  325.     }

  326.     if (s->picture.data[0])

  327.         s->avctx->release_buffer(s->avctx, &s->picture);

  328.     if ((ret = s->avctx->get_buffer(s->avctx, &s->picture)) < 0) {

  329.         av_log(s->avctx, AV_LOG_ERROR, "get_buffer() failed\n");

  330.         return ret;

  331.     }

  332.     if (s->avctx->pix_fmt == PIX_FMT_PAL8) {

  333.         if (s->palette_is_set) {

  334.             memcpy(s->picture.data[1], s->palette, sizeof(s->palette));

  335.         } else {

  336.             /* make default grayscale pal */

  337.             pal = (uint32_t *) s->picture.data[1];

  338.             for (i = 0; i < 1<<s->bpp; i++)

  339.                 pal[i] = 0xFF << 24 | i * 255 / ((1<<s->bpp) - 1) * 0x010101;

  340.         }

  341.     }

  342.     return 0;

  343. }

  344. 

  345. static int tiff_decode_tag(TiffContext *s, const uint8_t *start, const uint8_t *buf, const uint8_t *end_buf)

  346. {

  347.     unsigned tag, type, count, off, value = 0;

  348.     int i, j;

  349.     uint32_t *pal;

  350.     const uint8_t *rp, *gp, *bp;

  351. 

  352.     if (end_buf - buf < 12)

  353.         return -1;

  354.     tag = tget_short(&buf, s->le);

  355.     type = tget_short(&buf, s->le);

  356.     count = tget_long(&buf, s->le);

  357.     off = tget_long(&buf, s->le);

  358. 

  359.     if (type == 0 || type >= FF_ARRAY_ELEMS(type_sizes)) {

  360.         av_log(s->avctx, AV_LOG_DEBUG, "Unknown tiff type (%u) encountered\n", type);

  361.         return 0;

  362.     }

  363. 

  364.     if(count == 1){

  365.         switch(type){

  366.         case TIFF_BYTE:

  367.         case TIFF_SHORT:

  368.             buf -= 4;

  369.             value = tget(&buf, type, s->le);

  370.             buf = NULL;

  371.             break;

  372.         case TIFF_LONG:

  373.             value = off;

  374.             buf = NULL;

  375.             break;

  376.         case TIFF_STRING:

  377.             if(count <= 4){

  378.                 buf -= 4;

  379.                 break;

  380.             }

  381.         default:

  382.             value = UINT_MAX;

  383.             buf = start + off;

  384.         }

  385.     } else {

  386.         if (count <= 4 && type_sizes[type] * count <= 4) {

  387.             buf -= 4;

  388.         } else {

  389.             buf = start + off;

  390.         }

  391.     }

  392. 

  393.     if(buf && (buf < start || buf > end_buf)){

  394.         av_log(s->avctx, AV_LOG_ERROR, "Tag referencing position outside the image\n");

  395.         return -1;

  396.     }

  397. 

  398.     switch(tag){

  399.     case TIFF_WIDTH:

  400.         s->width = value;

  401.         break;

  402.     case TIFF_HEIGHT:

  403.         s->height = value;

  404.         break;

  405.     case TIFF_BPP:

  406.         s->bppcount = count;

  407.         if(count > 4){

  408.             av_log(s->avctx, AV_LOG_ERROR, "This format is not supported (bpp=%d, %d components)\n", s->bpp, count);

  409.             return -1;

  410.         }

  411.         if(count == 1) s->bpp = value;

  412.         else{

  413.             switch(type){

  414.             case TIFF_BYTE:

  415.                 s->bpp = (off & 0xFF) + ((off >> 8) & 0xFF) + ((off >> 16) & 0xFF) + ((off >> 24) & 0xFF);

  416.                 break;

  417.             case TIFF_SHORT:

  418.             case TIFF_LONG:

  419.                 s->bpp = 0;

  420.                 for(i = 0; i < count && buf < end_buf; i++) s->bpp += tget(&buf, type, s->le);

  421.                 break;

  422.             default:

  423.                 s->bpp = -1;

  424.             }

  425.         }

  426.         break;

  427.     case TIFF_SAMPLES_PER_PIXEL:

  428.         if (count != 1) {

  429.             av_log(s->avctx, AV_LOG_ERROR,

  430.                    "Samples per pixel requires a single value, many provided\n");

  431.             return AVERROR_INVALIDDATA;

  432.         }

  433.         if (s->bppcount == 1)

  434.             s->bpp *= value;

  435.         s->bppcount = value;

  436.         break;

  437.     case TIFF_COMPR:

  438.         s->compr = value;

  439.         s->predictor = 0;

  440.         switch(s->compr){

  441.         case TIFF_RAW:

  442.         case TIFF_PACKBITS:

  443.         case TIFF_LZW:

  444.         case TIFF_CCITT_RLE:

  445.             break;

  446.         case TIFF_G3:

  447.         case TIFF_G4:

  448.             s->fax_opts = 0;

  449.             break;

  450.         case TIFF_DEFLATE:

  451.         case TIFF_ADOBE_DEFLATE:

  452. #if CONFIG_ZLIB

  453.             break;

  454. #else

  455.             av_log(s->avctx, AV_LOG_ERROR, "Deflate: ZLib not compiled in\n");

  456.             return -1;

  457. #endif

  458.         case TIFF_JPEG:

  459.         case TIFF_NEWJPEG:

  460.             av_log(s->avctx, AV_LOG_ERROR, "JPEG compression is not supported\n");

  461.             return -1;

  462.         default:

  463.             av_log(s->avctx, AV_LOG_ERROR, "Unknown compression method %i\n", s->compr);

  464.             return -1;

  465.         }

  466.         break;

  467.     case TIFF_ROWSPERSTRIP:

  468.         if (type == TIFF_LONG && value == UINT_MAX)

  469.             value = s->avctx->height;

  470.         if(value < 1){

  471.             av_log(s->avctx, AV_LOG_ERROR, "Incorrect value of rows per strip\n");

  472.             return -1;

  473.         }

  474.         s->rps = value;

  475.         break;

  476.     case TIFF_STRIP_OFFS:

  477.         if(count == 1){

  478.             s->stripdata = NULL;

  479.             s->stripoff = value;

  480.         }else

  481.             s->stripdata = start + off;

  482.         s->strips = count;

  483.         if(s->strips == 1) s->rps = s->height;

  484.         s->sot = type;

  485.         if(s->stripdata > end_buf){

  486.             av_log(s->avctx, AV_LOG_ERROR, "Tag referencing position outside the image\n");

  487.             return -1;

  488.         }

  489.         break;

  490.     case TIFF_STRIP_SIZE:

  491.         if(count == 1){

  492.             s->stripsizes = NULL;

  493.             s->stripsize = value;

  494.             s->strips = 1;

  495.         }else{

  496.             s->stripsizes = start + off;

  497.         }

  498.         s->strips = count;

  499.         s->sstype = type;

  500.         if(s->stripsizes > end_buf){

  501.             av_log(s->avctx, AV_LOG_ERROR, "Tag referencing position outside the image\n");

  502.             return -1;

  503.         }

  504.         break;

  505.     case TIFF_TILE_BYTE_COUNTS:

  506.     case TIFF_TILE_LENGTH:

  507.     case TIFF_TILE_OFFSETS:

  508.     case TIFF_TILE_WIDTH:

  509.         av_log(s->avctx, AV_LOG_ERROR, "Tiled images are not supported\n");

  510.         return AVERROR_PATCHWELCOME;

  511.         break;

  512.     case TIFF_PREDICTOR:

  513.         s->predictor = value;

  514.         break;

  515.     case TIFF_INVERT:

  516.         switch(value){

  517.         case 0:

  518.             s->invert = 1;

  519.             break;

  520.         case 1:

  521.             s->invert = 0;

  522.             break;

  523.         case 2:

  524.         case 3:

  525.             break;

  526.         default:

  527.             av_log(s->avctx, AV_LOG_ERROR, "Color mode %d is not supported\n", value);

  528.             return -1;

  529.         }

  530.         break;

  531.     case TIFF_FILL_ORDER:

  532.         if(value < 1 || value > 2){

  533.             av_log(s->avctx, AV_LOG_ERROR, "Unknown FillOrder value %d, trying default one\n", value);

  534.             value = 1;

  535.         }

  536.         s->fill_order = value - 1;

  537.         break;

  538.     case TIFF_PAL:

  539.         pal = (uint32_t *) s->palette;

  540.         off = type_sizes[type];

  541.         if (count / 3 > 256 || end_buf - buf < count / 3 * off * 3)

  542.             return -1;

  543.         rp = buf;

  544.         gp = buf + count / 3 * off;

  545.         bp = buf + count / 3 * off * 2;

  546.         off = (type_sizes[type] - 1) << 3;

  547.         for(i = 0; i < count / 3; i++){

  548.             j = 0xff << 24;

  549.             j |= (tget(&rp, type, s->le) >> off) << 16;

  550.             j |= (tget(&gp, type, s->le) >> off) << 8;

  551.             j |= tget(&bp, type, s->le) >> off;

  552.             pal[i] = j;

  553.         }

  554.         s->palette_is_set = 1;

  555.         break;

  556.     case TIFF_PLANAR:

  557.         if(value == 2){

  558.             av_log(s->avctx, AV_LOG_ERROR, "Planar format is not supported\n");

  559.             return -1;

  560.         }

  561.         break;

  562.     case TIFF_T4OPTIONS:

  563.         if(s->compr == TIFF_G3)

  564.             s->fax_opts = value;

  565.         break;

  566.     case TIFF_T6OPTIONS:

  567.         if(s->compr == TIFF_G4)

  568.             s->fax_opts = value;

  569.         break;

  570.     default:

  571.         av_log(s->avctx, AV_LOG_DEBUG, "Unknown or unsupported tag %d/0X%0X\n", tag, tag);

  572.     }

  573.     return 0;

  574. }

  575. 

  576. static int decode_frame(AVCodecContext *avctx,

  577.                         void *data, int *data_size,

  578.                         AVPacket *avpkt)

  579. {

  580.     const uint8_t *buf = avpkt->data;

  581.     int buf_size = avpkt->size;

  582.     TiffContext * const s = avctx->priv_data;

  583.     AVFrame *picture = data;

  584.     AVFrame * const p = &s->picture;

  585.     const uint8_t *orig_buf = buf, *end_buf = buf + buf_size;

  586.     unsigned off;

  587.     int id, le, ret;

  588.     int i, j, entries;

  589.     int stride;

  590.     unsigned soff, ssize;

  591.     uint8_t *dst;

  592. 

  593.     //parse image header

  594.     if (end_buf - buf < 8)

  595.         return AVERROR_INVALIDDATA;

  596.     id = AV_RL16(buf); buf += 2;

  597.     if(id == 0x4949) le = 1;

  598.     else if(id == 0x4D4D) le = 0;

  599.     else{

  600.         av_log(avctx, AV_LOG_ERROR, "TIFF header not found\n");

  601.         return -1;

  602.     }

  603.     s->le = le;

  604.     s->invert = 0;

  605.     s->compr = TIFF_RAW;

  606.     s->fill_order = 0;

  607.     // As TIFF 6.0 specification puts it "An arbitrary but carefully chosen number

  608.     // that further identifies the file as a TIFF file"

  609.     if(tget_short(&buf, le) != 42){

  610.         av_log(avctx, AV_LOG_ERROR, "The answer to life, universe and everything is not correct!\n");

  611.         return -1;

  612.     }

  613.     // Reset these pointers so we can tell if they were set this frame

  614.     s->stripsizes = s->stripdata = NULL;

  615.     /* parse image file directory */

  616.     off = tget_long(&buf, le);

  617.     if (off >= UINT_MAX - 14 || end_buf - orig_buf < off + 14) {

  618.         av_log(avctx, AV_LOG_ERROR, "IFD offset is greater than image size\n");

  619.         return AVERROR_INVALIDDATA;

  620.     }

  621.     buf = orig_buf + off;

  622.     entries = tget_short(&buf, le);

  623.     for(i = 0; i < entries; i++){

  624.         if(tiff_decode_tag(s, orig_buf, buf, end_buf) < 0)

  625.             return -1;

  626.         buf += 12;

  627.     }

  628.     if(!s->stripdata && !s->stripoff){

  629.         av_log(avctx, AV_LOG_ERROR, "Image data is missing\n");

  630.         return -1;

  631.     }

  632.     /* now we have the data and may start decoding */

  633.     if ((ret = init_image(s)) < 0)

  634.         return ret;

  635. 

  636.     if(s->strips == 1 && !s->stripsize){

  637.         av_log(avctx, AV_LOG_WARNING, "Image data size missing\n");

  638.         s->stripsize = buf_size - s->stripoff;

  639.     }

  640.     stride = p->linesize[0];

  641.     dst = p->data[0];

  642.     for(i = 0; i < s->height; i += s->rps){

  643.         if(s->stripsizes) {

  644.             if (s->stripsizes >= end_buf)

  645.                 return AVERROR_INVALIDDATA;

  646.             ssize = tget(&s->stripsizes, s->sstype, s->le);

  647.         } else

  648.             ssize = s->stripsize;

  649. 

  650.         if(s->stripdata){

  651.             if (s->stripdata >= end_buf)

  652.                 return AVERROR_INVALIDDATA;

  653.             soff = tget(&s->stripdata, s->sot, s->le);

  654.         }else

  655.             soff = s->stripoff;

  656. 

  657.         if (soff > buf_size || ssize > buf_size - soff) {

  658.             av_log(avctx, AV_LOG_ERROR, "Invalid strip size/offset\n");

  659.             return -1;

  660.         }

  661.         if(tiff_unpack_strip(s, dst, stride, orig_buf + soff, ssize, FFMIN(s->rps, s->height - i)) < 0)

  662.             break;

  663.         dst += s->rps * stride;

  664.     }

  665.     if(s->predictor == 2){

  666.         dst = p->data[0];

  667.         soff = s->bpp >> 3;

  668.         ssize = s->width * soff;

  669.         if (s->avctx->pix_fmt == PIX_FMT_RGB48LE ||

  670.             s->avctx->pix_fmt == PIX_FMT_RGBA64LE) {

  671.             for (i = 0; i < s->height; i++) {

  672.                 for (j = soff; j < ssize; j += 2)

  673.                     AV_WL16(dst + j, AV_RL16(dst + j) + AV_RL16(dst + j - soff));

  674.                 dst += stride;

  675.             }

  676.         } else if (s->avctx->pix_fmt == PIX_FMT_RGB48BE ||

  677.                    s->avctx->pix_fmt == PIX_FMT_RGBA64BE) {

  678.             for (i = 0; i < s->height; i++) {

  679.                 for (j = soff; j < ssize; j += 2)

  680.                     AV_WB16(dst + j, AV_RB16(dst + j) + AV_RB16(dst + j - soff));

  681.                 dst += stride;

  682.             }

  683.         } else {

  684.             for(i = 0; i < s->height; i++) {

  685.                 for(j = soff; j < ssize; j++)

  686.                     dst[j] += dst[j - soff];

  687.                 dst += stride;

  688.             }

  689.         }

  690.     }

  691. 

  692.     if(s->invert){

  693.         dst = s->picture.data[0];

  694.         for(i = 0; i < s->height; i++){

  695.             for(j = 0; j < s->picture.linesize[0]; j++)

  696.                 dst[j] = (s->avctx->pix_fmt == PIX_FMT_PAL8 ? (1<<s->bpp) - 1 : 255) - dst[j];

  697.             dst += s->picture.linesize[0];

  698.         }

  699.     }

  700.     *picture   = s->picture;

  701.     *data_size = sizeof(AVPicture);

  702. 

  703.     return buf_size;

  704. }

  705. 

  706. static av_cold int tiff_init(AVCodecContext *avctx){

  707.     TiffContext *s = avctx->priv_data;

  708. 

  709.     s->width = 0;

  710.     s->height = 0;

  711.     s->avctx = avctx;

  712.     avcodec_get_frame_defaults(&s->picture);

  713.     avctx->coded_frame = &s->picture;

  714.     ff_lzw_decode_open(&s->lzw);

  715.     ff_ccitt_unpack_init();

  716. 

  717.     return 0;

  718. }

  719. 

  720. static av_cold int tiff_end(AVCodecContext *avctx)

  721. {

  722.     TiffContext * const s = avctx->priv_data;

  723. 

  724.     ff_lzw_decode_close(&s->lzw);

  725.     if(s->picture.data[0])

  726.         avctx->release_buffer(avctx, &s->picture);

  727.     return 0;

  728. }

  729. 

  730. AVCodec ff_tiff_decoder = {

  731.     .name           = "tiff",

  732.     .type           = AVMEDIA_TYPE_VIDEO,

  733.     .id             = CODEC_ID_TIFF,

  734.     .priv_data_size = sizeof(TiffContext),

  735.     .init           = tiff_init,

  736.     .close          = tiff_end,

  737.     .decode         = decode_frame,

  738.     .capabilities   = CODEC_CAP_DR1,

  739.     .long_name      = NULL_IF_CONFIG_SMALL("TIFF image"),

  740. };