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FFmpeg/libavcodec/j2kdec.c

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  1. /*

  2.  * JPEG2000 image decoder

  3.  * Copyright (c) 2007 Kamil Nowosad

  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. 

  22. /**

  23.  * JPEG2000 image decoder

  24.  * @file

  25.  * @author Kamil Nowosad

  26.  */

  27. 

  28. #include "avcodec.h"

  29. #include "bytestream.h"

  30. #include "j2k.h"

  31. #include "libavutil/common.h"

  32. 

  33. #define JP2_SIG_TYPE    0x6A502020

  34. #define JP2_SIG_VALUE   0x0D0A870A

  35. #define JP2_CODESTREAM  0x6A703263

  36. 

  37. #define HAD_COC 0x01

  38. #define HAD_QCC 0x02

  39. 

  40. typedef struct {

  41.    J2kComponent *comp;

  42.    uint8_t properties[4];

  43.    J2kCodingStyle codsty[4];

  44.    J2kQuantStyle  qntsty[4];

  45. } J2kTile;

  46. 

  47. typedef struct {

  48.     AVCodecContext *avctx;

  49.     AVFrame picture;

  50. 

  51.     int width, height; ///< image width and height

  52.     int image_offset_x, image_offset_y;

  53.     int tile_offset_x, tile_offset_y;

  54.     uint8_t cbps[4]; ///< bits per sample in particular components

  55.     uint8_t sgnd[4]; ///< if a component is signed

  56.     uint8_t properties[4];

  57.     int cdx[4], cdy[4];

  58.     int precision;

  59.     int ncomponents;

  60.     int tile_width, tile_height; ///< tile size

  61.     int numXtiles, numYtiles;

  62.     int maxtilelen;

  63. 

  64.     J2kCodingStyle codsty[4];

  65.     J2kQuantStyle  qntsty[4];

  66. 

  67.     uint8_t *buf_start;

  68.     uint8_t *buf;

  69.     uint8_t *buf_end;

  70.     int bit_index;

  71. 

  72.     int16_t curtileno;

  73. 

  74.     J2kTile *tile;

  75. } J2kDecoderContext;

  76. 

  77. static int get_bits(J2kDecoderContext *s, int n)

  78. {

  79.     int res = 0;

  80.     if (s->buf_end - s->buf < ((n - s->bit_index) >> 8))

  81.         return AVERROR(EINVAL);

  82.     while (--n >= 0){

  83.         res <<= 1;

  84.         if (s->bit_index == 0){

  85.             s->bit_index = 7 + (*s->buf != 0xff);

  86.             s->buf++;

  87.         }

  88.         s->bit_index--;

  89.         res |= (*s->buf >> s->bit_index) & 1;

  90.     }

  91.     return res;

  92. }

  93. 

  94. static void j2k_flush(J2kDecoderContext *s)

  95. {

  96.     if (*s->buf == 0xff)

  97.         s->buf++;

  98.     s->bit_index = 8;

  99.     s->buf++;

  100. }

  101. #if 0

  102. void printcomp(J2kComponent *comp)

  103. {

  104.     int i;

  105.     for (i = 0; i < comp->y1 - comp->y0; i++)

  106.         ff_j2k_printv(comp->data + i * (comp->x1 - comp->x0), comp->x1 - comp->x0);

  107. }

  108. 

  109. static void nspaces(FILE *fd, int n)

  110. {

  111.     while(n--) putc(' ', fd);

  112. }

  113. 

  114. static void dump(J2kDecoderContext *s, FILE *fd)

  115. {

  116.     int tileno, compno, reslevelno, bandno, precno;

  117.     fprintf(fd, "XSiz = %d, YSiz = %d, tile_width = %d, tile_height = %d\n"

  118.                 "numXtiles = %d, numYtiles = %d, ncomponents = %d\n"

  119.                 "tiles:\n",

  120.             s->width, s->height, s->tile_width, s->tile_height,

  121.             s->numXtiles, s->numYtiles, s->ncomponents);

  122.     for (tileno = 0; tileno < s->numXtiles * s->numYtiles; tileno++){

  123.         J2kTile *tile = s->tile + tileno;

  124.         nspaces(fd, 2);

  125.         fprintf(fd, "tile %d:\n", tileno);

  126.         for(compno = 0; compno < s->ncomponents; compno++){

  127.             J2kComponent *comp = tile->comp + compno;

  128.             nspaces(fd, 4);

  129.             fprintf(fd, "component %d:\n", compno);

  130.             nspaces(fd, 4);

  131.             fprintf(fd, "x0 = %d, x1 = %d, y0 = %d, y1 = %d\n",

  132.                         comp->x0, comp->x1, comp->y0, comp->y1);

  133.             for(reslevelno = 0; reslevelno < codsty->nreslevels; reslevelno++){

  134.                 J2kResLevel *reslevel = comp->reslevel + reslevelno;

  135.                 nspaces(fd, 6);

  136.                 fprintf(fd, "reslevel %d:\n", reslevelno);

  137.                 nspaces(fd, 6);

  138.                 fprintf(fd, "x0 = %d, x1 = %d, y0 = %d, y1 = %d, nbands = %d\n",

  139.                         reslevel->x0, reslevel->x1, reslevel->y0,

  140.                         reslevel->y1, reslevel->nbands);

  141.                 for(bandno = 0; bandno < reslevel->nbands; bandno++){

  142.                     J2kBand *band = reslevel->band + bandno;

  143.                     nspaces(fd, 8);

  144.                     fprintf(fd, "band %d:\n", bandno);

  145.                     nspaces(fd, 8);

  146.                     fprintf(fd, "x0 = %d, x1 = %d, y0 = %d, y1 = %d,"

  147.                                 "codeblock_width = %d, codeblock_height = %d cblknx = %d cblkny = %d\n",

  148.                                 band->x0, band->x1,

  149.                                 band->y0, band->y1,

  150.                                 band->codeblock_width, band->codeblock_height,

  151.                                 band->cblknx, band->cblkny);

  152.                     for (precno = 0; precno < reslevel->num_precincts_x * reslevel->num_precincts_y; precno++){

  153.                         J2kPrec *prec = band->prec + precno;

  154.                         nspaces(fd, 10);

  155.                         fprintf(fd, "prec %d:\n", precno);

  156.                         nspaces(fd, 10);

  157.                         fprintf(fd, "xi0 = %d, xi1 = %d, yi0 = %d, yi1 = %d\n",

  158.                                      prec->xi0, prec->xi1, prec->yi0, prec->yi1);

  159.                     }

  160.                 }

  161.             }

  162.         }

  163.     }

  164. }

  165. #endif

  166. 

  167. /** decode the value stored in node */

  168. static int tag_tree_decode(J2kDecoderContext *s, J2kTgtNode *node, int threshold)

  169. {

  170.     J2kTgtNode *stack[30];

  171.     int sp = -1, curval = 0;

  172. 

  173.     while(node && !node->vis){

  174.         stack[++sp] = node;

  175.         node = node->parent;

  176.     }

  177. 

  178.     if (node)

  179.         curval = node->val;

  180.     else

  181.         curval = stack[sp]->val;

  182. 

  183.     while(curval < threshold && sp >= 0){

  184.         if (curval < stack[sp]->val)

  185.             curval = stack[sp]->val;

  186.         while (curval < threshold){

  187.             int ret;

  188.             if ((ret = get_bits(s, 1)) > 0){

  189.                 stack[sp]->vis++;

  190.                 break;

  191.             } else if (!ret)

  192.                 curval++;

  193.             else

  194.                 return ret;

  195.         }

  196.         stack[sp]->val = curval;

  197.         sp--;

  198.     }

  199.     return curval;

  200. }

  201. 

  202. /* marker segments */

  203. /** get sizes and offsets of image, tiles; number of components */

  204. static int get_siz(J2kDecoderContext *s)

  205. {

  206.     int i, ret;

  207. 

  208.     if (s->buf_end - s->buf < 36)

  209.         return AVERROR(EINVAL);

  210. 

  211.                         bytestream_get_be16(&s->buf); // Rsiz (skipped)

  212.              s->width = bytestream_get_be32(&s->buf); // width

  213.             s->height = bytestream_get_be32(&s->buf); // height

  214.     s->image_offset_x = bytestream_get_be32(&s->buf); // X0Siz

  215.     s->image_offset_y = bytestream_get_be32(&s->buf); // Y0Siz

  216. 

  217.         s->tile_width = bytestream_get_be32(&s->buf); // XTSiz

  218.        s->tile_height = bytestream_get_be32(&s->buf); // YTSiz

  219.      s->tile_offset_x = bytestream_get_be32(&s->buf); // XT0Siz

  220.      s->tile_offset_y = bytestream_get_be32(&s->buf); // YT0Siz

  221.        s->ncomponents = bytestream_get_be16(&s->buf); // CSiz

  222. 

  223.     if (s->buf_end - s->buf < 2 * s->ncomponents)

  224.         return AVERROR(EINVAL);

  225. 

  226.     for (i = 0; i < s->ncomponents; i++){ // Ssiz_i XRsiz_i, YRsiz_i

  227.         uint8_t x = bytestream_get_byte(&s->buf);

  228.         s->cbps[i] = (x & 0x7f) + 1;

  229.         s->precision = FFMAX(s->cbps[i], s->precision);

  230.         s->sgnd[i] = (x & 0x80) == 1;

  231.         s->cdx[i] = bytestream_get_byte(&s->buf);

  232.         s->cdy[i] = bytestream_get_byte(&s->buf);

  233.     }

  234. 

  235.     s->numXtiles = ff_j2k_ceildiv(s->width - s->tile_offset_x, s->tile_width);

  236.     s->numYtiles = ff_j2k_ceildiv(s->height - s->tile_offset_y, s->tile_height);

  237. 

  238.     s->tile = av_mallocz(s->numXtiles * s->numYtiles * sizeof(J2kTile));

  239.     if (!s->tile)

  240.         return AVERROR(ENOMEM);

  241. 

  242.     for (i = 0; i < s->numXtiles * s->numYtiles; i++){

  243.         J2kTile *tile = s->tile + i;

  244. 

  245.         tile->comp = av_mallocz(s->ncomponents * sizeof(J2kComponent));

  246.         if (!tile->comp)

  247.             return AVERROR(ENOMEM);

  248.     }

  249. 

  250.     s->avctx->width = s->width - s->image_offset_x;

  251.     s->avctx->height = s->height - s->image_offset_y;

  252. 

  253.     switch(s->ncomponents){

  254.         case 1: if (s->precision > 8) {

  255.                     s->avctx->pix_fmt    = PIX_FMT_GRAY16;

  256.                 } else s->avctx->pix_fmt = PIX_FMT_GRAY8;

  257.                 break;

  258.         case 3: if (s->precision > 8) {

  259.                     s->avctx->pix_fmt    = PIX_FMT_RGB48;

  260.                 } else s->avctx->pix_fmt = PIX_FMT_RGB24;

  261.                 break;

  262.         case 4: s->avctx->pix_fmt = PIX_FMT_BGRA; break;

  263.     }

  264. 

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

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

  267. 

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

  269.         return ret;

  270. 

  271.     s->picture.pict_type = FF_I_TYPE;

  272.     s->picture.key_frame = 1;

  273. 

  274.     return 0;

  275. }

  276. 

  277. /** get common part for COD and COC segments */

  278. static int get_cox(J2kDecoderContext *s, J2kCodingStyle *c)

  279. {

  280.     if (s->buf_end - s->buf < 5)

  281.         return AVERROR(EINVAL);

  282.           c->nreslevels = bytestream_get_byte(&s->buf) + 1; // num of resolution levels - 1

  283.      c->log2_cblk_width = bytestream_get_byte(&s->buf) + 2; // cblk width

  284.     c->log2_cblk_height = bytestream_get_byte(&s->buf) + 2; // cblk height

  285. 

  286.     c->cblk_style = bytestream_get_byte(&s->buf);

  287.     if (c->cblk_style != 0){ // cblk style

  288.         av_log(s->avctx, AV_LOG_ERROR, "no extra cblk styles supported\n");

  289.         return -1;

  290.     }

  291.     c->transform = bytestream_get_byte(&s->buf); // transformation

  292.     if (c->csty & J2K_CSTY_PREC) {

  293.         int i;

  294.         for (i = 0; i < c->nreslevels; i++)

  295.             bytestream_get_byte(&s->buf);

  296.     }

  297.     return 0;

  298. }

  299. 

  300. /** get coding parameters for a particular tile or whole image*/

  301. static int get_cod(J2kDecoderContext *s, J2kCodingStyle *c, uint8_t *properties)

  302. {

  303.     J2kCodingStyle tmp;

  304.     int compno;

  305. 

  306.     if (s->buf_end - s->buf < 5)

  307.         return AVERROR(EINVAL);

  308. 

  309.     tmp.log2_prec_width  =

  310.     tmp.log2_prec_height = 15;

  311. 

  312.     tmp.csty = bytestream_get_byte(&s->buf);

  313. 

  314.     if (bytestream_get_byte(&s->buf)){ // progression level

  315.         av_log(s->avctx, AV_LOG_ERROR, "only LRCP progression supported\n");

  316.         return -1;

  317.     }

  318. 

  319.     tmp.nlayers = bytestream_get_be16(&s->buf);

  320.         tmp.mct = bytestream_get_byte(&s->buf); // multiple component transformation

  321. 

  322.     get_cox(s, &tmp);

  323.     for (compno = 0; compno < s->ncomponents; compno++){

  324.         if (!(properties[compno] & HAD_COC))

  325.             memcpy(c + compno, &tmp, sizeof(J2kCodingStyle));

  326.     }

  327.     return 0;

  328. }

  329. 

  330. /** get coding parameters for a component in the whole image on a particular tile */

  331. static int get_coc(J2kDecoderContext *s, J2kCodingStyle *c, uint8_t *properties)

  332. {

  333.     int compno;

  334. 

  335.     if (s->buf_end - s->buf < 2)

  336.         return AVERROR(EINVAL);

  337. 

  338.     compno = bytestream_get_byte(&s->buf);

  339. 

  340.     c += compno;

  341.     c->csty = bytestream_get_byte(&s->buf);

  342.     get_cox(s, c);

  343. 

  344.     properties[compno] |= HAD_COC;

  345.     return 0;

  346. }

  347. 

  348. /** get common part for QCD and QCC segments */

  349. static int get_qcx(J2kDecoderContext *s, int n, J2kQuantStyle *q)

  350. {

  351.     int i, x;

  352. 

  353.     if (s->buf_end - s->buf < 1)

  354.         return AVERROR(EINVAL);

  355. 

  356.     x = bytestream_get_byte(&s->buf); // Sqcd

  357. 

  358.     q->nguardbits = x >> 5;

  359.       q->quantsty = x & 0x1f;

  360. 

  361.     if (q->quantsty == J2K_QSTY_NONE){

  362.         n -= 3;

  363.         if (s->buf_end - s->buf < n)

  364.             return AVERROR(EINVAL);

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

  366.             q->expn[i] = bytestream_get_byte(&s->buf) >> 3;

  367.     } else if (q->quantsty == J2K_QSTY_SI){

  368.         if (s->buf_end - s->buf < 2)

  369.             return AVERROR(EINVAL);

  370.         x = bytestream_get_be16(&s->buf);

  371.         q->expn[0] = x >> 11;

  372.         q->mant[0] = x & 0x7ff;

  373.         for (i = 1; i < 32 * 3; i++){

  374.             int curexpn = FFMAX(0, q->expn[0] - (i-1)/3);

  375.             q->expn[i] = curexpn;

  376.             q->mant[i] = q->mant[0];

  377.         }

  378.     } else{

  379.         n = (n - 3) >> 1;

  380.         if (s->buf_end - s->buf < n)

  381.             return AVERROR(EINVAL);

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

  383.             x = bytestream_get_be16(&s->buf);

  384.             q->expn[i] = x >> 11;

  385.             q->mant[i] = x & 0x7ff;

  386.         }

  387.     }

  388.     return 0;

  389. }

  390. 

  391. /** get quantization parameters for a particular tile or a whole image */

  392. static int get_qcd(J2kDecoderContext *s, int n, J2kQuantStyle *q, uint8_t *properties)

  393. {

  394.     J2kQuantStyle tmp;

  395.     int compno;

  396. 

  397.     if (get_qcx(s, n, &tmp))

  398.         return -1;

  399.     for (compno = 0; compno < s->ncomponents; compno++)

  400.         if (!(properties[compno] & HAD_QCC))

  401.             memcpy(q + compno, &tmp, sizeof(J2kQuantStyle));

  402.     return 0;

  403. }

  404. 

  405. /** get quantization parameters for a component in the whole image on in a particular tile */

  406. static int get_qcc(J2kDecoderContext *s, int n, J2kQuantStyle *q, uint8_t *properties)

  407. {

  408.     int compno;

  409. 

  410.     if (s->buf_end - s->buf < 1)

  411.         return AVERROR(EINVAL);

  412. 

  413.     compno = bytestream_get_byte(&s->buf);

  414.     properties[compno] |= HAD_QCC;

  415.     return get_qcx(s, n-1, q+compno);

  416. }

  417. 

  418. /** get start of tile segment */

  419. static uint8_t get_sot(J2kDecoderContext *s)

  420. {

  421.     if (s->buf_end - s->buf < 4)

  422.         return AVERROR(EINVAL);

  423. 

  424.     s->curtileno = bytestream_get_be16(&s->buf); ///< Isot

  425. 

  426.     s->buf += 4; ///< Psot (ignored)

  427. 

  428.     if (!bytestream_get_byte(&s->buf)){ ///< TPsot

  429.         J2kTile *tile = s->tile + s->curtileno;

  430. 

  431.         /* copy defaults */

  432.         memcpy(tile->codsty, s->codsty, s->ncomponents * sizeof(J2kCodingStyle));

  433.         memcpy(tile->qntsty, s->qntsty, s->ncomponents * sizeof(J2kQuantStyle));

  434.     }

  435.     bytestream_get_byte(&s->buf); ///< TNsot

  436. 

  437.     return 0;

  438. }

  439. 

  440. static int init_tile(J2kDecoderContext *s, int tileno)

  441. {

  442.     int compno,

  443.         tilex = tileno % s->numXtiles,

  444.         tiley = tileno / s->numXtiles;

  445.     J2kTile *tile = s->tile + tileno;

  446. 

  447.     if (!tile->comp)

  448.         return AVERROR(ENOMEM);

  449.     for (compno = 0; compno < s->ncomponents; compno++){

  450.         J2kComponent *comp = tile->comp + compno;

  451.         J2kCodingStyle *codsty = tile->codsty + compno;

  452.         J2kQuantStyle  *qntsty = tile->qntsty + compno;

  453.         int ret; // global bandno

  454. 

  455.         comp->coord[0][0] = FFMAX(tilex * s->tile_width + s->tile_offset_x, s->image_offset_x);

  456.         comp->coord[0][1] = FFMIN((tilex+1)*s->tile_width + s->tile_offset_x, s->width);

  457.         comp->coord[1][0] = FFMAX(tiley * s->tile_height + s->tile_offset_y, s->image_offset_y);

  458.         comp->coord[1][1] = FFMIN((tiley+1)*s->tile_height + s->tile_offset_y, s->height);

  459. 

  460.         if (ret = ff_j2k_init_component(comp, codsty, qntsty, s->cbps[compno], s->cdx[compno], s->cdy[compno]))

  461.             return ret;

  462.     }

  463.     return 0;

  464. }

  465. 

  466. /** read the number of coding passes */

  467. static int getnpasses(J2kDecoderContext *s)

  468. {

  469.     int num;

  470.     if (!get_bits(s, 1))

  471.         return 1;

  472.     if (!get_bits(s, 1))

  473.         return 2;

  474.     if ((num = get_bits(s, 2)) != 3)

  475.         return num < 0 ? num : 3 + num;

  476.     if ((num = get_bits(s, 5)) != 31)

  477.         return num < 0 ? num : 6 + num;

  478.     num = get_bits(s, 7);

  479.     return num < 0 ? num : 37 + num;

  480. }

  481. 

  482. static int getlblockinc(J2kDecoderContext *s)

  483. {

  484.     int res = 0, ret;

  485.     while (ret = get_bits(s, 1)){

  486.         if (ret < 0)

  487.             return ret;

  488.         res++;

  489.     }

  490.     return res;

  491. }

  492. 

  493. static int decode_packet(J2kDecoderContext *s, J2kCodingStyle *codsty, J2kResLevel *rlevel, int precno,

  494.                          int layno, uint8_t *expn, int numgbits)

  495. {

  496.     int bandno, cblkny, cblknx, cblkno, ret;

  497. 

  498.     if (!(ret = get_bits(s, 1))){

  499.         j2k_flush(s);

  500.         return 0;

  501.     } else if (ret < 0)

  502.         return ret;

  503. 

  504.     for (bandno = 0; bandno < rlevel->nbands; bandno++){

  505.         J2kBand *band = rlevel->band + bandno;

  506.         J2kPrec *prec = band->prec + precno;

  507.         int pos = 0;

  508. 

  509.         if (band->coord[0][0] == band->coord[0][1]

  510.         ||  band->coord[1][0] == band->coord[1][1])

  511.             continue;

  512. 

  513.         for (cblkny = prec->yi0; cblkny < prec->yi1; cblkny++)

  514.             for(cblknx = prec->xi0, cblkno = cblkny * band->cblknx + cblknx; cblknx < prec->xi1; cblknx++, cblkno++, pos++){

  515.                 J2kCblk *cblk = band->cblk + cblkno;

  516.                 int incl, newpasses, llen;

  517. 

  518.                 if (cblk->npasses)

  519.                     incl = get_bits(s, 1);

  520.                 else

  521.                     incl = tag_tree_decode(s, prec->cblkincl + pos, layno+1) == layno;

  522.                 if (!incl)

  523.                     continue;

  524.                 else if (incl < 0)

  525.                     return incl;

  526. 

  527.                 if (!cblk->npasses)

  528.                     cblk->nonzerobits = expn[bandno] + numgbits - 1 - tag_tree_decode(s, prec->zerobits + pos, 100);

  529.                 if ((newpasses = getnpasses(s)) < 0)

  530.                     return newpasses;

  531.                 if ((llen = getlblockinc(s)) < 0)

  532.                     return llen;

  533.                 cblk->lblock += llen;

  534.                 if ((ret = get_bits(s, av_log2(newpasses) + cblk->lblock)) < 0)

  535.                     return ret;

  536.                 cblk->lengthinc = ret;

  537.                 cblk->npasses += newpasses;

  538.             }

  539.     }

  540.     j2k_flush(s);

  541. 

  542.     if (codsty->csty & J2K_CSTY_EPH) {

  543.         if (AV_RB16(s->buf) == J2K_EPH) {

  544.             s->buf += 2;

  545.         } else {

  546.             av_log(s->avctx, AV_LOG_ERROR, "EPH marker not found.\n");

  547.         }

  548.     }

  549. 

  550.     for (bandno = 0; bandno < rlevel->nbands; bandno++){

  551.         J2kBand *band = rlevel->band + bandno;

  552.         int yi, cblknw = band->prec[precno].xi1 - band->prec[precno].xi0;

  553.         for (yi = band->prec[precno].yi0; yi < band->prec[precno].yi1; yi++){

  554.             int xi;

  555.             for (xi = band->prec[precno].xi0; xi < band->prec[precno].xi1; xi++){

  556.                 J2kCblk *cblk = band->cblk + yi * cblknw + xi;

  557.                 if (s->buf_end - s->buf < cblk->lengthinc)

  558.                     return AVERROR(EINVAL);

  559.                 bytestream_get_buffer(&s->buf, cblk->data, cblk->lengthinc);

  560.                 cblk->length += cblk->lengthinc;

  561.                 cblk->lengthinc = 0;

  562.             }

  563.         }

  564.     }

  565.     return 0;

  566. }

  567. 

  568. static int decode_packets(J2kDecoderContext *s, J2kTile *tile)

  569. {

  570.     int layno, reslevelno, compno, precno, ok_reslevel;

  571.     s->bit_index = 8;

  572.     for (layno = 0; layno < tile->codsty[0].nlayers; layno++){

  573.         ok_reslevel = 1;

  574.         for (reslevelno = 0; ok_reslevel; reslevelno++){

  575.             ok_reslevel = 0;

  576.             for (compno = 0; compno < s->ncomponents; compno++){

  577.                 J2kCodingStyle *codsty = tile->codsty + compno;

  578.                 J2kQuantStyle  *qntsty = tile->qntsty + compno;

  579.                 if (reslevelno < codsty->nreslevels){

  580.                     J2kResLevel *rlevel = tile->comp[compno].reslevel + reslevelno;

  581.                     ok_reslevel = 1;

  582.                     for (precno = 0; precno < rlevel->num_precincts_x * rlevel->num_precincts_y; precno++){

  583.                         if (decode_packet(s, codsty, rlevel, precno, layno, qntsty->expn +

  584.                                           (reslevelno ? 3*(reslevelno-1)+1 : 0), qntsty->nguardbits))

  585.                             return -1;

  586.                     }

  587.                 }

  588.             }

  589.         }

  590.     }

  591.     return 0;

  592. }

  593. 

  594. /* TIER-1 routines */

  595. static void decode_sigpass(J2kT1Context *t1, int width, int height, int bpno, int bandno, int bpass_csty_symbol,

  596.                            int vert_causal_ctx_csty_symbol)

  597. {

  598.     int mask = 3 << (bpno - 1), y0, x, y;

  599. 

  600.     for (y0 = 0; y0 < height; y0 += 4)

  601.         for (x = 0; x < width; x++)

  602.             for (y = y0; y < height && y < y0+4; y++){

  603.                 if ((t1->flags[y+1][x+1] & J2K_T1_SIG_NB)

  604.                 && !(t1->flags[y+1][x+1] & (J2K_T1_SIG | J2K_T1_VIS))){

  605.                     int vert_causal_ctx_csty_loc_symbol = vert_causal_ctx_csty_symbol && (x == 3 && y == 3);

  606.                     if (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1], bandno,

  607.                                       vert_causal_ctx_csty_loc_symbol))){

  608.                         int xorbit, ctxno = ff_j2k_getsgnctxno(t1->flags[y+1][x+1], &xorbit);

  609.                         if (bpass_csty_symbol)

  610.                              t1->data[y][x] = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ? -mask : mask;

  611.                         else

  612.                              t1->data[y][x] = (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ^ xorbit) ?

  613.                                                -mask : mask;

  614. 

  615.                         ff_j2k_set_significant(t1, x, y, t1->data[y][x] < 0);

  616.                     }

  617.                     t1->flags[y+1][x+1] |= J2K_T1_VIS;

  618.                 }

  619.             }

  620. }

  621. 

  622. static void decode_refpass(J2kT1Context *t1, int width, int height, int bpno)

  623. {

  624.     int phalf, nhalf;

  625.     int y0, x, y;

  626. 

  627.     phalf = 1 << (bpno - 1);

  628.     nhalf = -phalf;

  629. 

  630.     for (y0 = 0; y0 < height; y0 += 4)

  631.         for (x = 0; x < width; x++)

  632.             for (y = y0; y < height && y < y0+4; y++){

  633.                 if ((t1->flags[y+1][x+1] & (J2K_T1_SIG | J2K_T1_VIS)) == J2K_T1_SIG){

  634.                     int ctxno = ff_j2k_getrefctxno(t1->flags[y+1][x+1]);

  635.                     int r = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ? phalf : nhalf;

  636.                     t1->data[y][x] += t1->data[y][x] < 0 ? -r : r;

  637.                     t1->flags[y+1][x+1] |= J2K_T1_REF;

  638.                 }

  639.             }

  640. }

  641. 

  642. static void decode_clnpass(J2kDecoderContext *s, J2kT1Context *t1, int width, int height,

  643.                            int bpno, int bandno, int seg_symbols)

  644. {

  645.     int mask = 3 << (bpno - 1), y0, x, y, runlen, dec;

  646. 

  647.     for (y0 = 0; y0 < height; y0 += 4) {

  648.         for (x = 0; x < width; x++){

  649.             if (y0 + 3 < height && !(

  650.             (t1->flags[y0+1][x+1] & (J2K_T1_SIG_NB | J2K_T1_VIS | J2K_T1_SIG)) ||

  651.             (t1->flags[y0+2][x+1] & (J2K_T1_SIG_NB | J2K_T1_VIS | J2K_T1_SIG)) ||

  652.             (t1->flags[y0+3][x+1] & (J2K_T1_SIG_NB | J2K_T1_VIS | J2K_T1_SIG)) ||

  653.             (t1->flags[y0+4][x+1] & (J2K_T1_SIG_NB | J2K_T1_VIS | J2K_T1_SIG)))){

  654.                 if (!ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_RL))

  655.                     continue;

  656.                 runlen = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  657.                 runlen = (runlen << 1) | ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  658.                 dec = 1;

  659.             } else{

  660.                 runlen = 0;

  661.                 dec = 0;

  662.             }

  663. 

  664.             for (y = y0 + runlen; y < y0 + 4 && y < height; y++){

  665.                 if (!dec){

  666.                     if (!(t1->flags[y+1][x+1] & (J2K_T1_SIG | J2K_T1_VIS)))

  667.                         dec = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ff_j2k_getnbctxno(t1->flags[y+1][x+1],

  668.                                                                                              bandno, 0));

  669.                 }

  670.                 if (dec){

  671.                     int xorbit, ctxno = ff_j2k_getsgnctxno(t1->flags[y+1][x+1], &xorbit);

  672.                     t1->data[y][x] = (ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + ctxno) ^ xorbit) ? -mask : mask;

  673.                     ff_j2k_set_significant(t1, x, y, t1->data[y][x] < 0);

  674.                 }

  675.                 dec = 0;

  676.                 t1->flags[y+1][x+1] &= ~J2K_T1_VIS;

  677.             }

  678.         }

  679.     }

  680.     if (seg_symbols) {

  681.         int val;

  682.         val = ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  683.         val = (val << 1) + ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  684.         val = (val << 1) + ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  685.         val = (val << 1) + ff_mqc_decode(&t1->mqc, t1->mqc.cx_states + MQC_CX_UNI);

  686.         if (val != 0xa) {

  687.             av_log(s->avctx, AV_LOG_ERROR,"Segmentation symbol value incorrect\n");

  688.         }

  689.     }

  690. }

  691. 

  692. static int decode_cblk(J2kDecoderContext *s, J2kCodingStyle *codsty, J2kT1Context *t1, J2kCblk *cblk,

  693.                        int width, int height, int bandpos)

  694. {

  695.     int passno = cblk->npasses, pass_t = 2, bpno = cblk->nonzerobits - 1, y, clnpass_cnt = 0;

  696. 

  697.     for (y = 0; y < height+2; y++)

  698.         memset(t1->flags[y], 0, (width+2)*sizeof(int));

  699. 

  700.     for (y = 0; y < height; y++)

  701.         memset(t1->data[y], 0, width*sizeof(int));

  702. 

  703.     ff_mqc_initdec(&t1->mqc, cblk->data);

  704.     cblk->data[cblk->length] = 0xff;

  705.     cblk->data[cblk->length+1] = 0xff;

  706. 

  707.     int bpass_csty_symbol = J2K_CBLK_BYPASS & codsty->cblk_style;

  708.     int vert_causal_ctx_csty_symbol = J2K_CBLK_VSC & codsty->cblk_style;

  709. 

  710.     while(passno--){

  711.         switch(pass_t){

  712.             case 0: decode_sigpass(t1, width, height, bpno+1, bandpos,

  713.                                   bpass_csty_symbol && (clnpass_cnt >= 4), vert_causal_ctx_csty_symbol);

  714.                     break;

  715.             case 1: decode_refpass(t1, width, height, bpno+1);

  716.                     if (bpass_csty_symbol && clnpass_cnt >= 4)

  717.                         ff_mqc_initdec(&t1->mqc, cblk->data);

  718.                     break;

  719.             case 2: decode_clnpass(s, t1, width, height, bpno+1, bandpos,

  720.                                    codsty->cblk_style & J2K_CBLK_SEGSYM);

  721.                     clnpass_cnt = clnpass_cnt + 1;

  722.                     if (bpass_csty_symbol && clnpass_cnt >= 4)

  723.                        ff_mqc_initdec(&t1->mqc, cblk->data);

  724.                     break;

  725.         }

  726. 

  727.         pass_t++;

  728.         if (pass_t == 3){

  729.             bpno--;

  730.             pass_t = 0;

  731.         }

  732.     }

  733.     return 0;

  734. }

  735. 

  736. static void mct_decode(J2kDecoderContext *s, J2kTile *tile)

  737. {

  738.     int i, *src[3], i0, i1, i2, csize = 1;

  739. 

  740.     for (i = 0; i < 3; i++)

  741.         src[i] = tile->comp[i].data;

  742. 

  743.     for (i = 0; i < 2; i++)

  744.         csize *= tile->comp[0].coord[i][1] - tile->comp[0].coord[i][0];

  745. 

  746.     if (tile->codsty[0].transform == FF_DWT97){

  747.         for (i = 0; i < csize; i++){

  748.             i0 = *src[0] + (*src[2] * 46802 >> 16);

  749.             i1 = *src[0] - (*src[1] * 22553 + *src[2] * 46802 >> 16);

  750.             i2 = *src[0] + (116130 * *src[1] >> 16);

  751.             *src[0]++ = i0;

  752.             *src[1]++ = i1;

  753.             *src[2]++ = i2;

  754.         }

  755.     } else{

  756.         for (i = 0; i < csize; i++){

  757.             i1 = *src[0] - (*src[2] + *src[1] >> 2);

  758.             i0 = i1 + *src[2];

  759.             i2 = i1 + *src[1];

  760.             *src[0]++ = i0;

  761.             *src[1]++ = i1;

  762.             *src[2]++ = i2;

  763.         }

  764.     }

  765. }

  766. 

  767. static int decode_tile(J2kDecoderContext *s, J2kTile *tile)

  768. {

  769.     int compno, reslevelno, bandno;

  770.     int x, y, *src[4];

  771.     uint8_t *line;

  772.     J2kT1Context t1;

  773. 

  774.     for (compno = 0; compno < s->ncomponents; compno++){

  775.         J2kComponent *comp = tile->comp + compno;

  776.         J2kCodingStyle *codsty = tile->codsty + compno;

  777. 

  778.         for (reslevelno = 0; reslevelno < codsty->nreslevels; reslevelno++){

  779.             J2kResLevel *rlevel = comp->reslevel + reslevelno;

  780.             for (bandno = 0; bandno < rlevel->nbands; bandno++){

  781.                 J2kBand *band = rlevel->band + bandno;

  782.                 int cblkx, cblky, cblkno=0, xx0, x0, xx1, y0, yy0, yy1, bandpos;

  783. 

  784.                 bandpos = bandno + (reslevelno > 0);

  785. 

  786.                 yy0 = bandno == 0 ? 0 : comp->reslevel[reslevelno-1].coord[1][1] - comp->reslevel[reslevelno-1].coord[1][0];

  787.                 y0 = yy0;

  788.                 yy1 = FFMIN(ff_j2k_ceildiv(band->coord[1][0] + 1, band->codeblock_height) * band->codeblock_height,

  789.                             band->coord[1][1]) - band->coord[1][0] + yy0;

  790. 

  791.                 if (band->coord[0][0] == band->coord[0][1] || band->coord[1][0] == band->coord[1][1])

  792.                     continue;

  793. 

  794.                 for (cblky = 0; cblky < band->cblkny; cblky++){

  795.                     if (reslevelno == 0 || bandno == 1)

  796.                         xx0 = 0;

  797.                     else

  798.                         xx0 = comp->reslevel[reslevelno-1].coord[0][1] - comp->reslevel[reslevelno-1].coord[0][0];

  799.                     x0 = xx0;

  800.                     xx1 = FFMIN(ff_j2k_ceildiv(band->coord[0][0] + 1, band->codeblock_width) * band->codeblock_width,

  801.                                 band->coord[0][1]) - band->coord[0][0] + xx0;

  802. 

  803.                     for (cblkx = 0; cblkx < band->cblknx; cblkx++, cblkno++){

  804.                         int y, x;

  805.                         decode_cblk(s, codsty, &t1, band->cblk + cblkno, xx1 - xx0, yy1 - yy0, bandpos);

  806.                         if (codsty->transform == FF_DWT53){

  807.                             for (y = yy0; y < yy1; y+=s->cdy[compno]){

  808.                                 int *ptr = t1.data[y-yy0];

  809.                                 for (x = xx0; x < xx1; x+=s->cdx[compno]){

  810.                                     comp->data[(comp->coord[0][1] - comp->coord[0][0]) * y + x] = *ptr++ >> 1;

  811.                                 }

  812.                             }

  813.                         } else{

  814.                             for (y = yy0; y < yy1; y+=s->cdy[compno]){

  815.                                 int *ptr = t1.data[y-yy0];

  816.                                 for (x = xx0; x < xx1; x+=s->cdx[compno]){

  817.                                     int tmp = ((int64_t)*ptr++) * ((int64_t)band->stepsize) >> 13, tmp2;

  818.                                     tmp2 = FFABS(tmp>>1) + FFABS(tmp&1);

  819.                                     comp->data[(comp->coord[0][1] - comp->coord[0][0]) * y + x] = tmp < 0 ? -tmp2 : tmp2;

  820.                                 }

  821.                             }

  822.                         }

  823.                         xx0 = xx1;

  824.                         xx1 = FFMIN(xx1 + band->codeblock_width, band->coord[0][1] - band->coord[0][0] + x0);

  825.                     }

  826.                     yy0 = yy1;

  827.                     yy1 = FFMIN(yy1 + band->codeblock_height, band->coord[1][1] - band->coord[1][0] + y0);

  828.                 }

  829.             }

  830.         }

  831.         ff_j2k_dwt_decode(&comp->dwt, comp->data);

  832.         src[compno] = comp->data;

  833.     }

  834.     if (tile->codsty[0].mct)

  835.         mct_decode(s, tile);

  836. 

  837.     if (s->avctx->pix_fmt == PIX_FMT_BGRA) // RGBA -> BGRA

  838.         FFSWAP(int *, src[0], src[2]);

  839. 

  840.     if (s->precision <= 8) {

  841.         for (compno = 0; compno < s->ncomponents; compno++){

  842.             y = tile->comp[compno].coord[1][0] - s->image_offset_y;

  843.             line = s->picture.data[0] + y * s->picture.linesize[0];

  844.             for (; y < tile->comp[compno].coord[1][1] - s->image_offset_y; y += s->cdy[compno]){

  845.                 uint8_t *dst;

  846. 

  847.                 x = tile->comp[compno].coord[0][0] - s->image_offset_x;

  848.                 dst = line + x * s->ncomponents + compno;

  849. 

  850.                 for (; x < tile->comp[compno].coord[0][1] - s->image_offset_x; x += s->cdx[compno]) {

  851.                     *src[compno] += 1 << (s->cbps[compno]-1);

  852.                     if (*src[compno] < 0)

  853.                         *src[compno] = 0;

  854.                     else if (*src[compno] >= (1 << s->cbps[compno]))

  855.                         *src[compno] = (1 << s->cbps[compno]) - 1;

  856.                     *dst = *src[compno]++;

  857.                     dst += s->ncomponents;

  858.                 }

  859.                 line += s->picture.linesize[0];

  860.             }

  861.         }

  862.     } else {

  863.         for (compno = 0; compno < s->ncomponents; compno++) {

  864.             y = tile->comp[compno].coord[1][0] - s->image_offset_y;

  865.             line = s->picture.data[0] + y * s->picture.linesize[0];

  866.             for (; y < tile->comp[compno].coord[1][1] - s->image_offset_y; y += s->cdy[compno]) {

  867.                 uint16_t *dst;

  868.                 x = tile->comp[compno].coord[0][0] - s->image_offset_x;

  869.                 dst = line + (x * s->ncomponents + compno) * 2;

  870.                 for (; x < tile->comp[compno].coord[0][1] - s->image_offset_x; x += s-> cdx[compno]) {

  871.                     int32_t val;

  872.                     val = *src[compno]++ << (16 - s->cbps[compno]);

  873.                     val += 1 << 15;

  874.                     val = av_clip(val, 0, (1 << 16) - 1);

  875.                     *dst = val;

  876.                     dst += s->ncomponents;

  877.                 }

  878.                 line += s->picture.linesize[0];

  879.             }

  880.         }

  881.     }

  882.     return 0;

  883. }

  884. 

  885. static void cleanup(J2kDecoderContext *s)

  886. {

  887.     int tileno, compno;

  888.     for (tileno = 0; tileno < s->numXtiles * s->numYtiles; tileno++){

  889.         for (compno = 0; compno < s->ncomponents; compno++){

  890.             J2kComponent *comp = s->tile[tileno].comp + compno;

  891.             J2kCodingStyle *codsty = s->tile[tileno].codsty + compno;

  892. 

  893.             ff_j2k_cleanup(comp, codsty);

  894.         }

  895.         av_freep(&s->tile[tileno].comp);

  896.     }

  897.     av_freep(&s->tile);

  898. }

  899. 

  900. static int decode_codestream(J2kDecoderContext *s)

  901. {

  902.     J2kCodingStyle *codsty = s->codsty;

  903.     J2kQuantStyle  *qntsty = s->qntsty;

  904.     uint8_t *properties = s->properties;

  905. 

  906.     for (;;){

  907.         int marker, len, ret = 0;

  908.         uint8_t *oldbuf;

  909.         if (s->buf_end - s->buf < 2){

  910.             av_log(s->avctx, AV_LOG_ERROR, "Missing EOC\n");

  911.             break;

  912.         }

  913. 

  914.         marker = bytestream_get_be16(&s->buf);

  915.         oldbuf = s->buf;

  916. 

  917.         if (marker == J2K_SOD){

  918.             J2kTile *tile = s->tile + s->curtileno;

  919.             if (ret = init_tile(s, s->curtileno))

  920.                 return ret;

  921.             if (ret = decode_packets(s, tile))

  922.                 return ret;

  923.             continue;

  924.         }

  925.         if (marker == J2K_EOC)

  926.             break;

  927. 

  928.         if (s->buf_end - s->buf < 2)

  929.             return AVERROR(EINVAL);

  930.         len = bytestream_get_be16(&s->buf);

  931.         switch(marker){

  932.             case J2K_SIZ:

  933.                 ret = get_siz(s); break;

  934.             case J2K_COC:

  935.                 ret = get_coc(s, codsty, properties); break;

  936.             case J2K_COD:

  937.                 ret = get_cod(s, codsty, properties); break;

  938.             case J2K_QCC:

  939.                 ret = get_qcc(s, len, qntsty, properties); break;

  940.             case J2K_QCD:

  941.                 ret = get_qcd(s, len, qntsty, properties); break;

  942.             case J2K_SOT:

  943.                 if (!(ret = get_sot(s))){

  944.                     codsty = s->tile[s->curtileno].codsty;

  945.                     qntsty = s->tile[s->curtileno].qntsty;

  946.                     properties = s->tile[s->curtileno].properties;

  947.                 }

  948.                 break;

  949.             case J2K_COM:

  950.                 // the comment is ignored

  951.                 s->buf += len - 2; break;

  952.             default:

  953.                 av_log(s->avctx, AV_LOG_ERROR, "unsupported marker 0x%.4X at pos 0x%x\n", marker, s->buf - s->buf_start - 4);

  954.                 s->buf += len - 2; break;

  955.         }

  956.         if (s->buf - oldbuf != len || ret){

  957.             av_log(s->avctx, AV_LOG_ERROR, "error during processing marker segment %.4x\n", marker);

  958.             return ret ? ret : -1;

  959.         }

  960.     }

  961.     return 0;

  962. }

  963. 

  964. static int jp2_find_codestream(J2kDecoderContext *s)

  965. {

  966.     int32_t atom_size;

  967.     int found_codestream = 0, search_range = 10;

  968. 

  969.     // skip jpeg2k signature atom

  970.     s->buf += 12;

  971. 

  972.     while(!found_codestream && search_range) {

  973.         atom_size = AV_RB32(s->buf);

  974.         if(AV_RB32(s->buf + 4) == JP2_CODESTREAM) {

  975.             found_codestream = 1;

  976.             s->buf += 8;

  977.         } else {

  978.             s->buf += atom_size;

  979.             search_range--;

  980.         }

  981.     }

  982. 

  983.     if(found_codestream)

  984.         return 1;

  985.     return 0;

  986. }

  987. 

  988. static int decode_frame(AVCodecContext *avctx,

  989.                         void *data, int *data_size,

  990.                         AVPacket *avpkt)

  991. {

  992.     J2kDecoderContext *s = avctx->priv_data;

  993.     AVFrame *picture = data;

  994.     int tileno, ret;

  995. 

  996.     s->avctx = avctx;

  997.     av_log(s->avctx, AV_LOG_DEBUG, "start\n");

  998. 

  999.     // init

  1000.     s->buf = s->buf_start = avpkt->data;

  1001.     s->buf_end = s->buf_start + avpkt->size;

  1002.     s->curtileno = -1;

  1003. 

  1004.     ff_j2k_init_tier1_luts();

  1005. 

  1006.     if (s->buf_end - s->buf < 2)

  1007.         return AVERROR(EINVAL);

  1008. 

  1009.     // check if the image is in jp2 format

  1010.     if((AV_RB32(s->buf) == 12) && (AV_RB32(s->buf + 4) == JP2_SIG_TYPE) &&

  1011.        (AV_RB32(s->buf + 8) == JP2_SIG_VALUE)) {

  1012.         if(!jp2_find_codestream(s)) {

  1013.             av_log(avctx, AV_LOG_ERROR, "couldn't find jpeg2k codestream atom\n");

  1014.             return -1;

  1015.         }

  1016.     }

  1017. 

  1018.     if (bytestream_get_be16(&s->buf) != J2K_SOC){

  1019.         av_log(avctx, AV_LOG_ERROR, "SOC marker not present\n");

  1020.         return -1;

  1021.     }

  1022.     if (ret = decode_codestream(s))

  1023.         return ret;

  1024. 

  1025.     for (tileno = 0; tileno < s->numXtiles * s->numYtiles; tileno++)

  1026.         if (ret = decode_tile(s, s->tile + tileno))

  1027.             return ret;

  1028. 

  1029.     cleanup(s);

  1030.     av_log(s->avctx, AV_LOG_DEBUG, "end\n");

  1031. 

  1032.     *data_size = sizeof(AVPicture);

  1033.     *picture = s->picture;

  1034. 

  1035.     return s->buf - s->buf_start;

  1036. }

  1037. 

  1038. static av_cold int j2kdec_init(AVCodecContext *avctx)

  1039. {

  1040.     J2kDecoderContext *s = avctx->priv_data;

  1041. 

  1042.     avcodec_get_frame_defaults((AVFrame*)&s->picture);

  1043.     avctx->coded_frame = (AVFrame*)&s->picture;

  1044.     return 0;

  1045. }

  1046. 

  1047. static av_cold int decode_end(AVCodecContext *avctx)

  1048. {

  1049.     J2kDecoderContext *s = avctx->priv_data;

  1050. 

  1051.     if (s->picture.data[0])

  1052.         avctx->release_buffer(avctx, &s->picture);

  1053. 

  1054.     return 0;

  1055. }

  1056. 

  1057. AVCodec ff_jpeg2000_decoder = {

  1058.     "j2k",

  1059.     AVMEDIA_TYPE_VIDEO,

  1060.     CODEC_ID_JPEG2000,

  1061.     sizeof(J2kDecoderContext),

  1062.     j2kdec_init,

  1063.     NULL,

  1064.     decode_end,

  1065.     decode_frame,

  1066.     .capabilities = CODEC_CAP_EXPERIMENTAL,

  1067.     .pix_fmts =

  1068.         (enum PixelFormat[]) {PIX_FMT_GRAY8, PIX_FMT_RGB24, -1}

  1069. };