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FFmpeg/libavcodec/tiff.c

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  1. /*

  2.  * TIFF image decoder

  3.  * Copyright (c) 2006 Konstantin Shishkov

  4.  *

  5.  * This file is part of Libav.

  6.  *

  7.  * Libav 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.  * Libav 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 Libav; if not, write to the Free Software

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

  20.  */

  21. 

  22. /**

  23.  * @file

  24.  * TIFF image decoder

  25.  * @author Konstantin Shishkov

  26.  */

  27. 

  28. #include "config.h"

  29. #if CONFIG_ZLIB

  30. #include <zlib.h>

  31. #endif

  32. 

  33. #include "libavutil/attributes.h"

  34. #include "libavutil/intreadwrite.h"

  35. #include "libavutil/imgutils.h"

  36. #include "avcodec.h"

  37. #include "bytestream.h"

  38. #include "faxcompr.h"

  39. #include "internal.h"

  40. #include "lzw.h"

  41. #include "mathops.h"

  42. #include "tiff.h"

  43. 

  44. typedef struct TiffContext {

  45.     AVCodecContext *avctx;

  46.     GetByteContext gb;

  47. 

  48.     int width, height;

  49.     unsigned int bpp, bppcount;

  50.     uint32_t palette[256];

  51.     int palette_is_set;

  52.     int le;

  53.     enum TiffCompr compr;

  54.     enum TiffPhotometric photometric;

  55.     int fax_opts;

  56.     int predictor;

  57.     int fill_order;

  58. 

  59.     int strips, rps, sstype;

  60.     int sot;

  61.     int stripsizesoff, stripsize, stripoff, strippos;

  62.     LZWState *lzw;

  63. } TiffContext;

  64. 

  65. static unsigned tget_short(GetByteContext *gb, int le)

  66. {

  67.     return le ? bytestream2_get_le16(gb) : bytestream2_get_be16(gb);

  68. }

  69. 

  70. static unsigned tget_long(GetByteContext *gb, int le)

  71. {

  72.     return le ? bytestream2_get_le32(gb) : bytestream2_get_be32(gb);

  73. }

  74. 

  75. static unsigned tget(GetByteContext *gb, int type, int le)

  76. {

  77.     switch (type) {

  78.     case TIFF_BYTE:  return bytestream2_get_byte(gb);

  79.     case TIFF_SHORT: return tget_short(gb, le);

  80.     case TIFF_LONG:  return tget_long(gb, le);

  81.     default:         return UINT_MAX;

  82.     }

  83. }

  84. 

  85. #if CONFIG_ZLIB

  86. static int tiff_uncompress(uint8_t *dst, unsigned long *len, const uint8_t *src,

  87.                            int size)

  88. {

  89.     z_stream zstream = { 0 };

  90.     int zret;

  91. 

  92.     zstream.next_in   = src;

  93.     zstream.avail_in  = size;

  94.     zstream.next_out  = dst;

  95.     zstream.avail_out = *len;

  96.     zret              = inflateInit(&zstream);

  97.     if (zret != Z_OK) {

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

  99.         return zret;

  100.     }

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

  102.     inflateEnd(&zstream);

  103.     *len = zstream.total_out;

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

  105. }

  106. 

  107. static int tiff_unpack_zlib(TiffContext *s, uint8_t *dst, int stride,

  108.                             const uint8_t *src, int size,

  109.                             int width, int lines)

  110. {

  111.     uint8_t *zbuf;

  112.     unsigned long outlen;

  113.     int ret, line;

  114.     outlen = width * lines;

  115.     zbuf   = av_malloc(outlen);

  116.     if (!zbuf)

  117.         return AVERROR(ENOMEM);

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

  119.     if (ret != Z_OK) {

  120.         av_log(s->avctx, AV_LOG_ERROR,

  121.                "Uncompressing failed (%lu of %lu) with error %d\n", outlen,

  122.                (unsigned long)width * lines, ret);

  123.         av_free(zbuf);

  124.         return AVERROR_UNKNOWN;

  125.     }

  126.     src = zbuf;

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

  128.         memcpy(dst, src, width);

  129.         dst += stride;

  130.         src += width;

  131.     }

  132.     av_free(zbuf);

  133.     return 0;

  134. }

  135. #endif

  136. 

  137. 

  138. static int tiff_unpack_fax(TiffContext *s, uint8_t *dst, int stride,

  139.                            const uint8_t *src, int size, int lines)

  140. {

  141.     int i, ret = 0;

  142.     uint8_t *src2 = av_malloc((unsigned)size +

  143.                               FF_INPUT_BUFFER_PADDING_SIZE);

  144. 

  145.     if (!src2) {

  146.         av_log(s->avctx, AV_LOG_ERROR,

  147.                "Error allocating temporary buffer\n");

  148.         return AVERROR(ENOMEM);

  149.     }

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

  151.         avpriv_request_sample(s->avctx, "Uncompressed fax mode");

  152.         av_free(src2);

  153.         return AVERROR_PATCHWELCOME;

  154.     }

  155.     if (!s->fill_order) {

  156.         memcpy(src2, src, size);

  157.     } else {

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

  159.             src2[i] = ff_reverse[src[i]];

  160.     }

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

  162.     ret = ff_ccitt_unpack(s->avctx, src2, size, dst, lines, stride,

  163.                           s->compr, s->fax_opts);

  164.     av_free(src2);

  165.     return ret;

  166. }

  167. 

  168. static int tiff_unpack_strip(TiffContext *s, uint8_t *dst, int stride,

  169.                              const uint8_t *src, int size, int lines)

  170. {

  171.     PutByteContext pb;

  172.     int c, line, pixels, code, ret;

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

  174. 

  175.     if (size <= 0)

  176.         return AVERROR_INVALIDDATA;

  177. 

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

  179. #if CONFIG_ZLIB

  180.         return tiff_unpack_zlib(s, dst, stride, src, size, width, lines);

  181. #else

  182.         av_log(s->avctx, AV_LOG_ERROR,

  183.                "zlib support not enabled, "

  184.                "deflate compression not supported\n");

  185.         return AVERROR(ENOSYS);

  186. #endif

  187.     }

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

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

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

  191.             return ret;

  192.         }

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

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

  195.             if (pixels < width) {

  196.                 av_log(s->avctx, AV_LOG_ERROR, "Decoded only %i bytes of %i\n",

  197.                        pixels, width);

  198.                 return AVERROR_INVALIDDATA;

  199.             }

  200.             dst += stride;

  201.         }

  202.         return 0;

  203.     }

  204.     if (s->compr == TIFF_CCITT_RLE ||

  205.         s->compr == TIFF_G3        ||

  206.         s->compr == TIFF_G4) {

  207.         return tiff_unpack_fax(s, dst, stride, src, size, lines);

  208.     }

  209. 

  210.     bytestream2_init(&s->gb, src, size);

  211.     bytestream2_init_writer(&pb, dst, stride * lines);

  212. 

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

  214.         if (bytestream2_get_bytes_left(&s->gb) == 0 || bytestream2_get_eof(&pb))

  215.             break;

  216.         bytestream2_seek_p(&pb, stride * line, SEEK_SET);

  217.         switch (s->compr) {

  218.         case TIFF_RAW:

  219.             if (!s->fill_order) {

  220.                 bytestream2_copy_buffer(&pb, &s->gb, width);

  221.             } else {

  222.                 int i;

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

  224.                     bytestream2_put_byte(&pb, ff_reverse[bytestream2_get_byte(&s->gb)]);

  225.             }

  226.             break;

  227.         case TIFF_PACKBITS:

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

  229.                 code = ff_u8_to_s8(bytestream2_get_byte(&s->gb));

  230.                 if (code >= 0) {

  231.                     code++;

  232.                     bytestream2_copy_buffer(&pb, &s->gb, code);

  233.                     pixels += code;

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

  235.                     code = (-code) + 1;

  236.                     c    = bytestream2_get_byte(&s->gb);

  237.                     bytestream2_set_buffer(&pb, c, code);

  238.                     pixels += code;

  239.                 }

  240.             }

  241.             break;

  242.         }

  243.     }

  244.     return 0;

  245. }

  246. 

  247. static int init_image(TiffContext *s, AVFrame *frame)

  248. {

  249.     int i, ret;

  250.     uint32_t *pal;

  251. 

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

  253.     case 11:

  254.         s->avctx->pix_fmt = AV_PIX_FMT_MONOBLACK;

  255.         break;

  256.     case 81:

  257.         s->avctx->pix_fmt = AV_PIX_FMT_PAL8;

  258.         break;

  259.     case 243:

  260.         s->avctx->pix_fmt = AV_PIX_FMT_RGB24;

  261.         break;

  262.     case 161:

  263.         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_GRAY16LE : AV_PIX_FMT_GRAY16BE;

  264.         break;

  265.     case 162:

  266.         s->avctx->pix_fmt = AV_PIX_FMT_YA8;

  267.         break;

  268.     case 322:

  269.         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_YA16LE : AV_PIX_FMT_YA16BE;

  270.         break;

  271.     case 324:

  272.         s->avctx->pix_fmt = AV_PIX_FMT_RGBA;

  273.         break;

  274.     case 483:

  275.         s->avctx->pix_fmt = s->le ? AV_PIX_FMT_RGB48LE : AV_PIX_FMT_RGB48BE;

  276.         break;

  277.     default:

  278.         av_log(s->avctx, AV_LOG_ERROR,

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

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

  281.         return AVERROR_INVALIDDATA;

  282.     }

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

  284.         ret = ff_set_dimensions(s->avctx, s->width, s->height);

  285.         if (ret < 0)

  286.             return ret;

  287.     }

  288.     if ((ret = ff_get_buffer(s->avctx, frame, 0)) < 0) {

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

  290.         return ret;

  291.     }

  292.     if (s->avctx->pix_fmt == AV_PIX_FMT_PAL8) {

  293.         if (s->palette_is_set) {

  294.             memcpy(frame->data[1], s->palette, sizeof(s->palette));

  295.         } else {

  296.             /* make default grayscale pal */

  297.             pal = (uint32_t *) frame->data[1];

  298.             for (i = 0; i < 256; i++)

  299.                 pal[i] = i * 0x010101;

  300.         }

  301.     }

  302.     return 0;

  303. }

  304. 

  305. static int tiff_decode_tag(TiffContext *s)

  306. {

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

  308.     int i, start;

  309. 

  310.     if (bytestream2_get_bytes_left(&s->gb) < 12)

  311.         return AVERROR_INVALIDDATA;

  312.     tag   = tget_short(&s->gb, s->le);

  313.     type  = tget_short(&s->gb, s->le);

  314.     count = tget_long(&s->gb, s->le);

  315.     off   = tget_long(&s->gb, s->le);

  316.     start = bytestream2_tell(&s->gb);

  317. 

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

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

  320.                type);

  321.         return 0;

  322.     }

  323. 

  324.     if (count == 1) {

  325.         switch (type) {

  326.         case TIFF_BYTE:

  327.         case TIFF_SHORT:

  328.             bytestream2_seek(&s->gb, -4, SEEK_CUR);

  329.             value = tget(&s->gb, type, s->le);

  330.             break;

  331.         case TIFF_LONG:

  332.             value = off;

  333.             break;

  334.         case TIFF_STRING:

  335.             if (count <= 4) {

  336.                 bytestream2_seek(&s->gb, -4, SEEK_CUR);

  337.                 break;

  338.             }

  339.         default:

  340.             value = UINT_MAX;

  341.             bytestream2_seek(&s->gb, off, SEEK_SET);

  342.         }

  343.     } else {

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

  345.             bytestream2_seek(&s->gb, -4, SEEK_CUR);

  346.         else

  347.             bytestream2_seek(&s->gb, off, SEEK_SET);

  348.     }

  349. 

  350.     switch (tag) {

  351.     case TIFF_WIDTH:

  352.         s->width = value;

  353.         break;

  354.     case TIFF_HEIGHT:

  355.         s->height = value;

  356.         break;

  357.     case TIFF_BPP:

  358.         s->bppcount = count;

  359.         if (count > 4) {

  360.             av_log(s->avctx, AV_LOG_ERROR,

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

  362.                    s->bpp, count);

  363.             return AVERROR_INVALIDDATA;

  364.         }

  365.         if (count == 1)

  366.             s->bpp = value;

  367.         else {

  368.             switch (type) {

  369.             case TIFF_BYTE:

  370.                 s->bpp = (off & 0xFF) + ((off >> 8) & 0xFF) +

  371.                          ((off >> 16) & 0xFF) + ((off >> 24) & 0xFF);

  372.                 break;

  373.             case TIFF_SHORT:

  374.             case TIFF_LONG:

  375.                 s->bpp = 0;

  376.                 for (i = 0; i < count; i++)

  377.                     s->bpp += tget(&s->gb, type, s->le);

  378.                 break;

  379.             default:

  380.                 s->bpp = -1;

  381.             }

  382.         }

  383.         break;

  384.     case TIFF_SAMPLES_PER_PIXEL:

  385.         if (count != 1) {

  386.             av_log(s->avctx, AV_LOG_ERROR,

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

  388.             return AVERROR_INVALIDDATA;

  389.         }

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

  391.             s->bpp *= value;

  392.         s->bppcount = value;

  393.         break;

  394.     case TIFF_COMPR:

  395.         s->compr     = value;

  396.         s->predictor = 0;

  397.         switch (s->compr) {

  398.         case TIFF_RAW:

  399.         case TIFF_PACKBITS:

  400.         case TIFF_LZW:

  401.         case TIFF_CCITT_RLE:

  402.             break;

  403.         case TIFF_G3:

  404.         case TIFF_G4:

  405.             s->fax_opts = 0;

  406.             break;

  407.         case TIFF_DEFLATE:

  408.         case TIFF_ADOBE_DEFLATE:

  409. #if CONFIG_ZLIB

  410.             break;

  411. #else

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

  413.             return AVERROR(ENOSYS);

  414. #endif

  415.         case TIFF_JPEG:

  416.         case TIFF_NEWJPEG:

  417.             avpriv_report_missing_feature(s->avctx, "JPEG compression");

  418.             return AVERROR_PATCHWELCOME;

  419.         default:

  420.             av_log(s->avctx, AV_LOG_ERROR, "Unknown compression method %i\n",

  421.                    s->compr);

  422.             return AVERROR_INVALIDDATA;

  423.         }

  424.         break;

  425.     case TIFF_ROWSPERSTRIP:

  426.         if (!value || (type == TIFF_LONG && value == UINT_MAX))

  427.             value = s->height;

  428.         s->rps = FFMIN(value, s->height);

  429.         break;

  430.     case TIFF_STRIP_OFFS:

  431.         if (count == 1) {

  432.             s->strippos = 0;

  433.             s->stripoff = value;

  434.         } else

  435.             s->strippos = off;

  436.         s->strips = count;

  437.         if (s->strips == 1)

  438.             s->rps = s->height;

  439.         s->sot = type;

  440.         break;

  441.     case TIFF_STRIP_SIZE:

  442.         if (count == 1) {

  443.             s->stripsizesoff = 0;

  444.             s->stripsize     = value;

  445.             s->strips        = 1;

  446.         } else {

  447.             s->stripsizesoff = off;

  448.         }

  449.         s->strips = count;

  450.         s->sstype = type;

  451.         break;

  452.     case TIFF_PREDICTOR:

  453.         s->predictor = value;

  454.         break;

  455.     case TIFF_PHOTOMETRIC:

  456.         switch (value) {

  457.         case TIFF_PHOTOMETRIC_WHITE_IS_ZERO:

  458.         case TIFF_PHOTOMETRIC_BLACK_IS_ZERO:

  459.         case TIFF_PHOTOMETRIC_RGB:

  460.         case TIFF_PHOTOMETRIC_PALETTE:

  461.             s->photometric = value;

  462.             break;

  463.         case TIFF_PHOTOMETRIC_ALPHA_MASK:

  464.         case TIFF_PHOTOMETRIC_SEPARATED:

  465.         case TIFF_PHOTOMETRIC_YCBCR:

  466.         case TIFF_PHOTOMETRIC_CIE_LAB:

  467.         case TIFF_PHOTOMETRIC_ICC_LAB:

  468.         case TIFF_PHOTOMETRIC_ITU_LAB:

  469.         case TIFF_PHOTOMETRIC_CFA:

  470.         case TIFF_PHOTOMETRIC_LOG_L:

  471.         case TIFF_PHOTOMETRIC_LOG_LUV:

  472.         case TIFF_PHOTOMETRIC_LINEAR_RAW:

  473.             avpriv_report_missing_feature(s->avctx,

  474.                                           "PhotometricInterpretation 0x%04X",

  475.                                           value);

  476.             return AVERROR_PATCHWELCOME;

  477.         default:

  478.             av_log(s->avctx, AV_LOG_ERROR, "PhotometricInterpretation %u is "

  479.                    "unknown\n", value);

  480.             return AVERROR_INVALIDDATA;

  481.         }

  482.         break;

  483.     case TIFF_FILL_ORDER:

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

  485.             av_log(s->avctx, AV_LOG_ERROR,

  486.                    "Unknown FillOrder value %d, trying default one\n", value);

  487.             value = 1;

  488.         }

  489.         s->fill_order = value - 1;

  490.         break;

  491.     case TIFF_PAL: {

  492.         GetByteContext pal_gb[3];

  493.         off = type_sizes[type];

  494.         if (count / 3 > 256 ||

  495.             bytestream2_get_bytes_left(&s->gb) < count / 3 * off * 3)

  496.             return AVERROR_INVALIDDATA;

  497.         pal_gb[0] = pal_gb[1] = pal_gb[2] = s->gb;

  498.         bytestream2_skip(&pal_gb[1], count / 3 * off);

  499.         bytestream2_skip(&pal_gb[2], count / 3 * off * 2);

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

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

  502.             uint32_t p = 0xFF000000;

  503.             p |= (tget(&pal_gb[0], type, s->le) >> off) << 16;

  504.             p |= (tget(&pal_gb[1], type, s->le) >> off) << 8;

  505.             p |=  tget(&pal_gb[2], type, s->le) >> off;

  506.             s->palette[i] = p;

  507.         }

  508.         s->palette_is_set = 1;

  509.         break;

  510.     }

  511.     case TIFF_PLANAR:

  512.         if (value == 2) {

  513.             avpriv_report_missing_feature(s->avctx, "Planar format");

  514.             return AVERROR_PATCHWELCOME;

  515.         }

  516.         break;

  517.     case TIFF_T4OPTIONS:

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

  519.             s->fax_opts = value;

  520.         break;

  521.     case TIFF_T6OPTIONS:

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

  523.             s->fax_opts = value;

  524.         break;

  525.     default:

  526.         if (s->avctx->err_recognition & AV_EF_EXPLODE) {

  527.             av_log(s->avctx, AV_LOG_ERROR,

  528.                    "Unknown or unsupported tag %d/0X%0X\n",

  529.                    tag, tag);

  530.             return AVERROR_INVALIDDATA;

  531.         }

  532.     }

  533.     bytestream2_seek(&s->gb, start, SEEK_SET);

  534.     return 0;

  535. }

  536. 

  537. static int decode_frame(AVCodecContext *avctx,

  538.                         void *data, int *got_frame, AVPacket *avpkt)

  539. {

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

  541.     AVFrame *const p = data;

  542.     unsigned off;

  543.     int id, le, ret;

  544.     int i, j, entries, stride;

  545.     unsigned soff, ssize;

  546.     uint8_t *dst;

  547.     GetByteContext stripsizes;

  548.     GetByteContext stripdata;

  549. 

  550.     bytestream2_init(&s->gb, avpkt->data, avpkt->size);

  551. 

  552.     // parse image header

  553.     if (avpkt->size < 8)

  554.         return AVERROR_INVALIDDATA;

  555.     id = bytestream2_get_le16(&s->gb);

  556.     if (id == 0x4949)

  557.         le = 1;

  558.     else if (id == 0x4D4D)

  559.         le = 0;

  560.     else {

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

  562.         return AVERROR_INVALIDDATA;

  563.     }

  564.     s->le          = le;

  565.     s->photometric = TIFF_PHOTOMETRIC_NONE;

  566.     s->compr       = TIFF_RAW;

  567.     s->fill_order  = 0;

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

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

  570.     if (tget_short(&s->gb, le) != 42) {

  571.         av_log(avctx, AV_LOG_ERROR,

  572.                "The answer to life, universe and everything is not correct!\n");

  573.         return AVERROR_INVALIDDATA;

  574.     }

  575.     // Reset these offsets so we can tell if they were set this frame

  576.     s->stripsizesoff = s->strippos = 0;

  577.     /* parse image file directory */

  578.     off = tget_long(&s->gb, le);

  579.     if (off >= UINT_MAX - 14 || avpkt->size < off + 14) {

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

  581.         return AVERROR_INVALIDDATA;

  582.     }

  583.     bytestream2_seek(&s->gb, off, SEEK_SET);

  584.     entries = tget_short(&s->gb, le);

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

  586.         if ((ret = tiff_decode_tag(s)) < 0)

  587.             return ret;

  588.     }

  589.     if (!s->strippos && !s->stripoff) {

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

  591.         return AVERROR_INVALIDDATA;

  592.     }

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

  594.     if ((ret = init_image(s, p)) < 0)

  595.         return ret;

  596. 

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

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

  599.         s->stripsize = avpkt->size - s->stripoff;

  600.     }

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

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

  603. 

  604.     if (s->stripsizesoff) {

  605.         if (s->stripsizesoff >= avpkt->size)

  606.             return AVERROR_INVALIDDATA;

  607.         bytestream2_init(&stripsizes, avpkt->data + s->stripsizesoff,

  608.                          avpkt->size - s->stripsizesoff);

  609.     }

  610.     if (s->strippos) {

  611.         if (s->strippos >= avpkt->size)

  612.             return AVERROR_INVALIDDATA;

  613.         bytestream2_init(&stripdata, avpkt->data + s->strippos,

  614.                          avpkt->size - s->strippos);

  615.     }

  616. 

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

  618.         if (s->stripsizesoff)

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

  620.         else

  621.             ssize = s->stripsize;

  622. 

  623.         if (s->strippos)

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

  625.         else

  626.             soff = s->stripoff;

  627. 

  628.         if (soff > avpkt->size || ssize > avpkt->size - soff) {

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

  630.             return AVERROR_INVALIDDATA;

  631.         }

  632.         if ((ret = tiff_unpack_strip(s, dst, stride, avpkt->data + soff, ssize,

  633.                                      FFMIN(s->rps, s->height - i))) < 0) {

  634.             if (avctx->err_recognition & AV_EF_EXPLODE)

  635.                 return ret;

  636.             break;

  637.         }

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

  639.     }

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

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

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

  643.         ssize = s->width * soff;

  644.         if (s->avctx->pix_fmt == AV_PIX_FMT_RGB48LE) {

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

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

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

  648.                 dst += stride;

  649.             }

  650.         } else if (s->avctx->pix_fmt == AV_PIX_FMT_RGB48BE) {

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

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

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

  654.                 dst += stride;

  655.             }

  656.         } else {

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

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

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

  660.                 dst += stride;

  661.             }

  662.         }

  663.     }

  664. 

  665.     if (s->photometric == TIFF_PHOTOMETRIC_WHITE_IS_ZERO) {

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

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

  668.             for (j = 0; j < p->linesize[0]; j++)

  669.                 dst[j] = 255 - dst[j];

  670.             dst += stride;

  671.         }

  672.     }

  673.     *got_frame = 1;

  674. 

  675.     return avpkt->size;

  676. }

  677. 

  678. static av_cold int tiff_init(AVCodecContext *avctx)

  679. {

  680.     TiffContext *s = avctx->priv_data;

  681. 

  682.     s->width  = 0;

  683.     s->height = 0;

  684.     s->avctx  = avctx;

  685.     ff_lzw_decode_open(&s->lzw);

  686.     ff_ccitt_unpack_init();

  687. 

  688.     return 0;

  689. }

  690. 

  691. static av_cold int tiff_end(AVCodecContext *avctx)

  692. {

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

  694. 

  695.     ff_lzw_decode_close(&s->lzw);

  696.     return 0;

  697. }

  698. 

  699. AVCodec ff_tiff_decoder = {

  700.     .name           = "tiff",

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

  702.     .type           = AVMEDIA_TYPE_VIDEO,

  703.     .id             = AV_CODEC_ID_TIFF,

  704.     .priv_data_size = sizeof(TiffContext),

  705.     .init           = tiff_init,

  706.     .close          = tiff_end,

  707.     .decode         = decode_frame,

  708.     .capabilities   = CODEC_CAP_DR1,

  709. };