falkTX
/
FFmpeg
mirror of https://github.com/falkTX/FFmpeg.git
1
0
Fork 0
Code Issues 0 Releases 338 Wiki Activity
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
67685 Commits
32 Branches
702MB
Tree: 12630fa821
Branches Tags
${ item.name }
Create branch ${ searchTerm }
from '12630fa821'
${ noResults }
FFmpeg/libavcodec/dvdsubdec.c

736 lines
22KB
Raw Blame History 

  1. /*

  2.  * DVD subtitle decoding

  3.  * Copyright (c) 2005 Fabrice Bellard

  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. #include "avcodec.h"

  23. #include "get_bits.h"

  24. #include "internal.h"

  25. 

  26. #include "libavutil/attributes.h"

  27. #include "libavutil/colorspace.h"

  28. #include "libavutil/opt.h"

  29. #include "libavutil/imgutils.h"

  30. #include "libavutil/avstring.h"

  31. #include "libavutil/bswap.h"

  32. 

  33. typedef struct DVDSubContext

  34. {

  35.   AVClass *class;

  36.   uint32_t palette[16];

  37.   char    *palette_str;

  38.   char    *ifo_str;

  39.   int      has_palette;

  40.   uint8_t  colormap[4];

  41.   uint8_t  alpha[256];

  42.   uint8_t *buf;

  43.   int      buf_size;

  44.   int      forced_subs_only;

  45. #ifdef DEBUG

  46.   int sub_id;

  47. #endif

  48. } DVDSubContext;

  49. 

  50. static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)

  51. {

  52.     const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;

  53.     uint8_t r, g, b;

  54.     int i, y, cb, cr;

  55.     int r_add, g_add, b_add;

  56. 

  57.     for (i = num_values; i > 0; i--) {

  58.         y = *ycbcr++;

  59.         cr = *ycbcr++;

  60.         cb = *ycbcr++;

  61.         YUV_TO_RGB1_CCIR(cb, cr);

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

  63.         *rgba++ = (*alpha++ << 24) | (r << 16) | (g << 8) | b;

  64.     }

  65. }

  66. 

  67. static int decode_run_2bit(GetBitContext *gb, int *color)

  68. {

  69.     unsigned int v, t;

  70. 

  71.     v = 0;

  72.     for (t = 1; v < t && t <= 0x40; t <<= 2)

  73.         v = (v << 4) | get_bits(gb, 4);

  74.     *color = v & 3;

  75.     if (v < 4) { /* Code for fill rest of line */

  76.         return INT_MAX;

  77.     }

  78.     return v >> 2;

  79. }

  80. 

  81. static int decode_run_8bit(GetBitContext *gb, int *color)

  82. {

  83.     int len;

  84.     int has_run = get_bits1(gb);

  85.     if (get_bits1(gb))

  86.         *color = get_bits(gb, 8);

  87.     else

  88.         *color = get_bits(gb, 2);

  89.     if (has_run) {

  90.         if (get_bits1(gb)) {

  91.             len = get_bits(gb, 7);

  92.             if (len == 0)

  93.                 len = INT_MAX;

  94.             else

  95.                 len += 9;

  96.         } else

  97.             len = get_bits(gb, 3) + 2;

  98.     } else

  99.         len = 1;

  100.     return len;

  101. }

  102. 

  103. static int decode_rle(uint8_t *bitmap, int linesize, int w, int h,

  104.                       const uint8_t *buf, int start, int buf_size, int is_8bit)

  105. {

  106.     GetBitContext gb;

  107.     int bit_len;

  108.     int x, y, len, color;

  109.     uint8_t *d;

  110. 

  111.     bit_len = (buf_size - start) * 8;

  112.     init_get_bits(&gb, buf + start, bit_len);

  113. 

  114.     x = 0;

  115.     y = 0;

  116.     d = bitmap;

  117.     for(;;) {

  118.         if (get_bits_count(&gb) > bit_len)

  119.             return -1;

  120.         if (is_8bit)

  121.             len = decode_run_8bit(&gb, &color);

  122.         else

  123.             len = decode_run_2bit(&gb, &color);

  124.         len = FFMIN(len, w - x);

  125.         memset(d + x, color, len);

  126.         x += len;

  127.         if (x >= w) {

  128.             y++;

  129.             if (y >= h)

  130.                 break;

  131.             d += linesize;

  132.             x = 0;

  133.             /* byte align */

  134.             align_get_bits(&gb);

  135.         }

  136.     }

  137.     return 0;

  138. }

  139. 

  140. static void guess_palette(DVDSubContext* ctx,

  141.                           uint32_t *rgba_palette,

  142.                           uint32_t subtitle_color)

  143. {

  144.     static const uint8_t level_map[4][4] = {

  145.         // this configuration (full range, lowest to highest) in tests

  146.         // seemed most common, so assume this

  147.         {0xff},

  148.         {0x00, 0xff},

  149.         {0x00, 0x80, 0xff},

  150.         {0x00, 0x55, 0xaa, 0xff},

  151.     };

  152.     uint8_t color_used[16] = { 0 };

  153.     int nb_opaque_colors, i, level, j, r, g, b;

  154.     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;

  155. 

  156.     if(ctx->has_palette) {

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

  158.             rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)

  159.                               | ((alpha[i] * 17U) << 24);

  160.         return;

  161.     }

  162. 

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

  164.         rgba_palette[i] = 0;

  165. 

  166.     nb_opaque_colors = 0;

  167.     for(i = 0; i < 4; i++) {

  168.         if (alpha[i] != 0 && !color_used[colormap[i]]) {

  169.             color_used[colormap[i]] = 1;

  170.             nb_opaque_colors++;

  171.         }

  172.     }

  173. 

  174.     if (nb_opaque_colors == 0)

  175.         return;

  176. 

  177.     j = 0;

  178.     memset(color_used, 0, 16);

  179.     for(i = 0; i < 4; i++) {

  180.         if (alpha[i] != 0) {

  181.             if (!color_used[colormap[i]])  {

  182.                 level = level_map[nb_opaque_colors][j];

  183.                 r = (((subtitle_color >> 16) & 0xff) * level) >> 8;

  184.                 g = (((subtitle_color >> 8) & 0xff) * level) >> 8;

  185.                 b = (((subtitle_color >> 0) & 0xff) * level) >> 8;

  186.                 rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24);

  187.                 color_used[colormap[i]] = (i + 1);

  188.                 j++;

  189.             } else {

  190.                 rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |

  191.                                     ((alpha[i] * 17) << 24);

  192.             }

  193.         }

  194.     }

  195. }

  196. 

  197. static void reset_rects(AVSubtitle *sub_header)

  198. {

  199.     int i;

  200. 

  201.     if (sub_header->rects) {

  202.         for (i = 0; i < sub_header->num_rects; i++) {

  203.             av_freep(&sub_header->rects[i]->pict.data[0]);

  204.             av_freep(&sub_header->rects[i]->pict.data[1]);

  205.             av_freep(&sub_header->rects[i]);

  206.         }

  207.         av_freep(&sub_header->rects);

  208.         sub_header->num_rects = 0;

  209.     }

  210. }

  211. 

  212. #define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))

  213. 

  214. static int decode_dvd_subtitles(DVDSubContext *ctx, AVSubtitle *sub_header,

  215.                                 const uint8_t *buf, int buf_size)

  216. {

  217.     int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;

  218.     int big_offsets, offset_size, is_8bit = 0;

  219.     const uint8_t *yuv_palette = NULL;

  220.     uint8_t *colormap = ctx->colormap, *alpha = ctx->alpha;

  221.     int date;

  222.     int i;

  223.     int is_menu = 0;

  224. 

  225.     if (buf_size < 10)

  226.         return -1;

  227. 

  228.     if (AV_RB16(buf) == 0) {   /* HD subpicture with 4-byte offsets */

  229.         big_offsets = 1;

  230.         offset_size = 4;

  231.         cmd_pos = 6;

  232.     } else {

  233.         big_offsets = 0;

  234.         offset_size = 2;

  235.         cmd_pos = 2;

  236.     }

  237. 

  238.     cmd_pos = READ_OFFSET(buf + cmd_pos);

  239. 

  240.     if (cmd_pos < 0 || cmd_pos > buf_size - 2 - offset_size)

  241.         return AVERROR(EAGAIN);

  242. 

  243.     while (cmd_pos > 0 && cmd_pos < buf_size - 2 - offset_size) {

  244.         date = AV_RB16(buf + cmd_pos);

  245.         next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);

  246.         av_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",

  247.                 cmd_pos, next_cmd_pos, date);

  248.         pos = cmd_pos + 2 + offset_size;

  249.         offset1 = -1;

  250.         offset2 = -1;

  251.         x1 = y1 = x2 = y2 = 0;

  252.         while (pos < buf_size) {

  253.             cmd = buf[pos++];

  254.             av_dlog(NULL, "cmd=%02x\n", cmd);

  255.             switch(cmd) {

  256.             case 0x00:

  257.                 /* menu subpicture */

  258.                 is_menu = 1;

  259.                 break;

  260.             case 0x01:

  261.                 /* set start date */

  262.                 sub_header->start_display_time = (date << 10) / 90;

  263.                 break;

  264.             case 0x02:

  265.                 /* set end date */

  266.                 sub_header->end_display_time = (date << 10) / 90;

  267.                 break;

  268.             case 0x03:

  269.                 /* set colormap */

  270.                 if ((buf_size - pos) < 2)

  271.                     goto fail;

  272.                 colormap[3] = buf[pos] >> 4;

  273.                 colormap[2] = buf[pos] & 0x0f;

  274.                 colormap[1] = buf[pos + 1] >> 4;

  275.                 colormap[0] = buf[pos + 1] & 0x0f;

  276.                 pos += 2;

  277.                 break;

  278.             case 0x04:

  279.                 /* set alpha */

  280.                 if ((buf_size - pos) < 2)

  281.                     goto fail;

  282.                 alpha[3] = buf[pos] >> 4;

  283.                 alpha[2] = buf[pos] & 0x0f;

  284.                 alpha[1] = buf[pos + 1] >> 4;

  285.                 alpha[0] = buf[pos + 1] & 0x0f;

  286.                 pos += 2;

  287.             av_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);

  288.                 break;

  289.             case 0x05:

  290.             case 0x85:

  291.                 if ((buf_size - pos) < 6)

  292.                     goto fail;

  293.                 x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);

  294.                 x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];

  295.                 y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);

  296.                 y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];

  297.                 if (cmd & 0x80)

  298.                     is_8bit = 1;

  299.                 av_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);

  300.                 pos += 6;

  301.                 break;

  302.             case 0x06:

  303.                 if ((buf_size - pos) < 4)

  304.                     goto fail;

  305.                 offset1 = AV_RB16(buf + pos);

  306.                 offset2 = AV_RB16(buf + pos + 2);

  307.                 av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);

  308.                 pos += 4;

  309.                 break;

  310.             case 0x86:

  311.                 if ((buf_size - pos) < 8)

  312.                     goto fail;

  313.                 offset1 = AV_RB32(buf + pos);

  314.                 offset2 = AV_RB32(buf + pos + 4);

  315.                 av_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);

  316.                 pos += 8;

  317.                 break;

  318. 

  319.             case 0x83:

  320.                 /* HD set palette */

  321.                 if ((buf_size - pos) < 768)

  322.                     goto fail;

  323.                 yuv_palette = buf + pos;

  324.                 pos += 768;

  325.                 break;

  326.             case 0x84:

  327.                 /* HD set contrast (alpha) */

  328.                 if ((buf_size - pos) < 256)

  329.                     goto fail;

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

  331.                     alpha[i] = 0xFF - buf[pos+i];

  332.                 pos += 256;

  333.                 break;

  334. 

  335.             case 0xff:

  336.                 goto the_end;

  337.             default:

  338.                 av_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);

  339.                 goto the_end;

  340.             }

  341.         }

  342.     the_end:

  343.         if (offset1 >= 0) {

  344.             int w, h;

  345.             uint8_t *bitmap;

  346. 

  347.             /* decode the bitmap */

  348.             w = x2 - x1 + 1;

  349.             if (w < 0)

  350.                 w = 0;

  351.             h = y2 - y1 + 1;

  352.             if (h < 0)

  353.                 h = 0;

  354.             if (w > 0 && h > 0) {

  355.                 reset_rects(sub_header);

  356. 

  357.                 bitmap = av_malloc(w * h);

  358.                 sub_header->rects = av_mallocz(sizeof(*sub_header->rects));

  359.                 sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));

  360.                 sub_header->num_rects = 1;

  361.                 sub_header->rects[0]->pict.data[0] = bitmap;

  362.                 decode_rle(bitmap, w * 2, w, (h + 1) / 2,

  363.                            buf, offset1, buf_size, is_8bit);

  364.                 decode_rle(bitmap + w, w * 2, w, h / 2,

  365.                            buf, offset2, buf_size, is_8bit);

  366.                 sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);

  367.                 if (is_8bit) {

  368.                     if (!yuv_palette)

  369.                         goto fail;

  370.                     sub_header->rects[0]->nb_colors = 256;

  371.                     yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);

  372.                 } else {

  373.                     sub_header->rects[0]->nb_colors = 4;

  374.                     guess_palette(ctx, (uint32_t*)sub_header->rects[0]->pict.data[1],

  375.                                   0xffff00);

  376.                 }

  377.                 sub_header->rects[0]->x = x1;

  378.                 sub_header->rects[0]->y = y1;

  379.                 sub_header->rects[0]->w = w;

  380.                 sub_header->rects[0]->h = h;

  381.                 sub_header->rects[0]->type = SUBTITLE_BITMAP;

  382.                 sub_header->rects[0]->pict.linesize[0] = w;

  383.                 sub_header->rects[0]->flags = is_menu ? AV_SUBTITLE_FLAG_FORCED : 0;

  384.             }

  385.         }

  386.         if (next_cmd_pos < cmd_pos) {

  387.             av_log(NULL, AV_LOG_ERROR, "Invalid command offset\n");

  388.             break;

  389.         }

  390.         if (next_cmd_pos == cmd_pos)

  391.             break;

  392.         cmd_pos = next_cmd_pos;

  393.     }

  394.     if (sub_header->num_rects > 0)

  395.         return is_menu;

  396.  fail:

  397.     reset_rects(sub_header);

  398.     return -1;

  399. }

  400. 

  401. static int is_transp(const uint8_t *buf, int pitch, int n,

  402.                      const uint8_t *transp_color)

  403. {

  404.     int i;

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

  406.         if (!transp_color[*buf])

  407.             return 0;

  408.         buf += pitch;

  409.     }

  410.     return 1;

  411. }

  412. 

  413. /* return 0 if empty rectangle, 1 if non empty */

  414. static int find_smallest_bounding_rectangle(AVSubtitle *s)

  415. {

  416.     uint8_t transp_color[256] = { 0 };

  417.     int y1, y2, x1, x2, y, w, h, i;

  418.     uint8_t *bitmap;

  419. 

  420.     if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)

  421.         return 0;

  422. 

  423.     for(i = 0; i < s->rects[0]->nb_colors; i++) {

  424.         if ((((uint32_t*)s->rects[0]->pict.data[1])[i] >> 24) == 0)

  425.             transp_color[i] = 1;

  426.     }

  427.     y1 = 0;

  428.     while (y1 < s->rects[0]->h && is_transp(s->rects[0]->pict.data[0] + y1 * s->rects[0]->pict.linesize[0],

  429.                                   1, s->rects[0]->w, transp_color))

  430.         y1++;

  431.     if (y1 == s->rects[0]->h) {

  432.         av_freep(&s->rects[0]->pict.data[0]);

  433.         s->rects[0]->w = s->rects[0]->h = 0;

  434.         return 0;

  435.     }

  436. 

  437.     y2 = s->rects[0]->h - 1;

  438.     while (y2 > 0 && is_transp(s->rects[0]->pict.data[0] + y2 * s->rects[0]->pict.linesize[0], 1,

  439.                                s->rects[0]->w, transp_color))

  440.         y2--;

  441.     x1 = 0;

  442.     while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->pict.data[0] + x1, s->rects[0]->pict.linesize[0],

  443.                                         s->rects[0]->h, transp_color))

  444.         x1++;

  445.     x2 = s->rects[0]->w - 1;

  446.     while (x2 > 0 && is_transp(s->rects[0]->pict.data[0] + x2, s->rects[0]->pict.linesize[0], s->rects[0]->h,

  447.                                   transp_color))

  448.         x2--;

  449.     w = x2 - x1 + 1;

  450.     h = y2 - y1 + 1;

  451.     bitmap = av_malloc(w * h);

  452.     if (!bitmap)

  453.         return 1;

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

  455.         memcpy(bitmap + w * y, s->rects[0]->pict.data[0] + x1 + (y1 + y) * s->rects[0]->pict.linesize[0], w);

  456.     }

  457.     av_freep(&s->rects[0]->pict.data[0]);

  458.     s->rects[0]->pict.data[0] = bitmap;

  459.     s->rects[0]->pict.linesize[0] = w;

  460.     s->rects[0]->w = w;

  461.     s->rects[0]->h = h;

  462.     s->rects[0]->x += x1;

  463.     s->rects[0]->y += y1;

  464.     return 1;

  465. }

  466. 

  467. #ifdef DEBUG

  468. #define ALPHA_MIX(A,BACK,FORE) (((255-(A)) * (BACK) + (A) * (FORE)) / 255)

  469. static void ppm_save(const char *filename, uint8_t *bitmap, int w, int h,

  470.                      uint32_t *rgba_palette)

  471. {

  472.     int x, y, alpha;

  473.     uint32_t v;

  474.     int back[3] = {0, 255, 0};  /* green background */

  475.     FILE *f;

  476. 

  477.     f = fopen(filename, "w");

  478.     if (!f) {

  479.         perror(filename);

  480.         return;

  481.     }

  482.     fprintf(f, "P6\n"

  483.             "%d %d\n"

  484.             "%d\n",

  485.             w, h, 255);

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

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

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

  489.             alpha = v >> 24;

  490.             putc(ALPHA_MIX(alpha, back[0], (v >> 16) & 0xff), f);

  491.             putc(ALPHA_MIX(alpha, back[1], (v >> 8) & 0xff), f);

  492.             putc(ALPHA_MIX(alpha, back[2], (v >> 0) & 0xff), f);

  493.         }

  494.     }

  495.     fclose(f);

  496. }

  497. #endif

  498. 

  499. static int append_to_cached_buf(AVCodecContext *avctx,

  500.                                 const uint8_t *buf, int buf_size)

  501. {

  502.     DVDSubContext *ctx = avctx->priv_data;

  503. 

  504.     if (ctx->buf_size > 0xffff - buf_size) {

  505.         av_log(avctx, AV_LOG_WARNING, "Attempt to reconstruct "

  506.                "too large SPU packets aborted.\n");

  507.         av_freep(&ctx->buf);

  508.         return AVERROR_INVALIDDATA;

  509.     }

  510.     ctx->buf = av_realloc(ctx->buf, ctx->buf_size + buf_size);

  511.     if (!ctx->buf)

  512.         return AVERROR(ENOMEM);

  513.     memcpy(ctx->buf + ctx->buf_size, buf, buf_size);

  514.     ctx->buf_size += buf_size;

  515.     return 0;

  516. }

  517. 

  518. static int dvdsub_decode(AVCodecContext *avctx,

  519.                          void *data, int *data_size,

  520.                          AVPacket *avpkt)

  521. {

  522.     DVDSubContext *ctx = avctx->priv_data;

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

  524.     int buf_size = avpkt->size;

  525.     AVSubtitle *sub = data;

  526.     int is_menu;

  527. 

  528.     if (ctx->buf) {

  529.         int ret = append_to_cached_buf(avctx, buf, buf_size);

  530.         if (ret < 0) {

  531.             *data_size = 0;

  532.             return ret;

  533.         }

  534.         buf = ctx->buf;

  535.         buf_size = ctx->buf_size;

  536.     }

  537. 

  538.     is_menu = decode_dvd_subtitles(ctx, sub, buf, buf_size);

  539.     if (is_menu == AVERROR(EAGAIN)) {

  540.         *data_size = 0;

  541.         return append_to_cached_buf(avctx, buf, buf_size);

  542.     }

  543. 

  544.     if (is_menu < 0) {

  545.     no_subtitle:

  546.         reset_rects(sub);

  547.         *data_size = 0;

  548. 

  549.         return buf_size;

  550.     }

  551.     if (!is_menu && find_smallest_bounding_rectangle(sub) == 0)

  552.         goto no_subtitle;

  553. 

  554.     if (ctx->forced_subs_only && !(sub->rects[0]->flags & AV_SUBTITLE_FLAG_FORCED))

  555.         goto no_subtitle;

  556. 

  557. #if defined(DEBUG)

  558.     {

  559.     char ppm_name[32];

  560. 

  561.     snprintf(ppm_name, sizeof(ppm_name), "/tmp/%05d.ppm", ctx->sub_id++);

  562.     av_dlog(NULL, "start=%d ms end =%d ms\n",

  563.             sub->start_display_time,

  564.             sub->end_display_time);

  565.     ppm_save(ppm_name, sub->rects[0]->pict.data[0],

  566.              sub->rects[0]->w, sub->rects[0]->h, (uint32_t*) sub->rects[0]->pict.data[1]);

  567.     }

  568. #endif

  569. 

  570.     av_freep(&ctx->buf);

  571.     ctx->buf_size = 0;

  572.     *data_size = 1;

  573.     return buf_size;

  574. }

  575. 

  576. static void parse_palette(DVDSubContext *ctx, char *p)

  577. {

  578.     int i;

  579. 

  580.     ctx->has_palette = 1;

  581.     for(i=0;i<16;i++) {

  582.         ctx->palette[i] = strtoul(p, &p, 16);

  583.         while(*p == ',' || av_isspace(*p))

  584.             p++;

  585.     }

  586. }

  587. 

  588. static int parse_ifo_palette(DVDSubContext *ctx, char *p)

  589. {

  590.     FILE *ifo;

  591.     char ifostr[12];

  592.     uint32_t sp_pgci, pgci, off_pgc, pgc;

  593.     uint8_t r, g, b, yuv[65], *buf;

  594.     int i, y, cb, cr, r_add, g_add, b_add;

  595.     int ret = 0;

  596.     const uint8_t *cm = ff_crop_tab + MAX_NEG_CROP;

  597. 

  598.     ctx->has_palette = 0;

  599.     if ((ifo = fopen(p, "r")) == NULL) {

  600.         av_log(ctx, AV_LOG_WARNING, "Unable to open IFO file \"%s\": %s\n", p, strerror(errno));

  601.         return AVERROR_EOF;

  602.     }

  603.     if (fread(ifostr, 12, 1, ifo) != 1 || memcmp(ifostr, "DVDVIDEO-VTS", 12)) {

  604.         av_log(ctx, AV_LOG_WARNING, "\"%s\" is not a proper IFO file\n", p);

  605.         ret = AVERROR_INVALIDDATA;

  606.         goto end;

  607.     }

  608.     fseek(ifo, 0xCC, SEEK_SET);

  609.     if (fread(&sp_pgci, 4, 1, ifo) == 1) {

  610.         pgci = av_be2ne32(sp_pgci) * 2048;

  611.         fseek(ifo, pgci + 0x0C, SEEK_SET);

  612.         if (fread(&off_pgc, 4, 1, ifo) == 1) {

  613.             pgc = pgci + av_be2ne32(off_pgc);

  614.             fseek(ifo, pgc + 0xA4, SEEK_SET);

  615.             if (fread(yuv, 64, 1, ifo) == 1) {

  616.                 buf = yuv;

  617.                 for(i=0; i<16; i++) {

  618.                     y  = *++buf;

  619.                     cr = *++buf;

  620.                     cb = *++buf;

  621.                     YUV_TO_RGB1_CCIR(cb, cr);

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

  623.                     ctx->palette[i] = (r << 16) + (g << 8) + b;

  624.                     buf++;

  625.                 }

  626.                 ctx->has_palette = 1;

  627.             }

  628.         }

  629.     }

  630.     if (ctx->has_palette == 0) {

  631.         av_log(ctx, AV_LOG_WARNING, "Failed to read palette from IFO file \"%s\"\n", p);

  632.         ret = AVERROR_INVALIDDATA;

  633.     }

  634. end:

  635.     fclose(ifo);

  636.     return ret;

  637. }

  638. 

  639. static int dvdsub_parse_extradata(AVCodecContext *avctx)

  640. {

  641.     DVDSubContext *ctx = (DVDSubContext*) avctx->priv_data;

  642.     char *dataorig, *data;

  643. 

  644.     if (!avctx->extradata || !avctx->extradata_size)

  645.         return 1;

  646. 

  647.     dataorig = data = av_malloc(avctx->extradata_size+1);

  648.     if (!data)

  649.         return AVERROR(ENOMEM);

  650.     memcpy(data, avctx->extradata, avctx->extradata_size);

  651.     data[avctx->extradata_size] = '\0';

  652. 

  653.     for(;;) {

  654.         int pos = strcspn(data, "\n\r");

  655.         if (pos==0 && *data==0)

  656.             break;

  657. 

  658.         if (strncmp("palette:", data, 8) == 0) {

  659.             parse_palette(ctx, data + 8);

  660.         } else if (strncmp("size:", data, 5) == 0) {

  661.             int w, h;

  662.             if (sscanf(data + 5, "%dx%d", &w, &h) == 2) {

  663.                int ret = ff_set_dimensions(avctx, w, h);

  664.                if (ret < 0) {

  665.                    av_free(dataorig);

  666.                    return ret;

  667.                }

  668.             }

  669.         }

  670. 

  671.         data += pos;

  672.         data += strspn(data, "\n\r");

  673.     }

  674. 

  675.     av_free(dataorig);

  676.     return 1;

  677. }

  678. 

  679. static av_cold int dvdsub_init(AVCodecContext *avctx)

  680. {

  681.     DVDSubContext *ctx = avctx->priv_data;

  682.     int ret;

  683. 

  684.     if ((ret = dvdsub_parse_extradata(avctx)) < 0)

  685.         return ret;

  686. 

  687.     if (ctx->ifo_str)

  688.         parse_ifo_palette(ctx, ctx->ifo_str);

  689.     if (ctx->palette_str)

  690.         parse_palette(ctx, ctx->palette_str);

  691.     if (ctx->has_palette) {

  692.         int i;

  693.         av_log(avctx, AV_LOG_DEBUG, "palette:");

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

  695.             av_log(avctx, AV_LOG_DEBUG, " 0x%06x", ctx->palette[i]);

  696.         av_log(avctx, AV_LOG_DEBUG, "\n");

  697.     }

  698. 

  699.     return 1;

  700. }

  701. 

  702. static av_cold int dvdsub_close(AVCodecContext *avctx)

  703. {

  704.     DVDSubContext *ctx = avctx->priv_data;

  705.     av_freep(&ctx->buf);

  706.     ctx->buf_size = 0;

  707.     return 0;

  708. }

  709. 

  710. #define OFFSET(field) offsetof(DVDSubContext, field)

  711. #define SD AV_OPT_FLAG_SUBTITLE_PARAM | AV_OPT_FLAG_DECODING_PARAM

  712. static const AVOption options[] = {

  713.     { "palette", "set the global palette", OFFSET(palette_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },

  714.     { "ifo_palette", "obtain the global palette from .IFO file", OFFSET(ifo_str), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, SD },

  715.     { "forced_subs_only", "Only show forced subtitles", OFFSET(forced_subs_only), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, SD},

  716.     { NULL }

  717. };

  718. static const AVClass dvdsub_class = {

  719.     .class_name = "dvdsubdec",

  720.     .item_name  = av_default_item_name,

  721.     .option     = options,

  722.     .version    = LIBAVUTIL_VERSION_INT,

  723. };

  724. 

  725. AVCodec ff_dvdsub_decoder = {

  726.     .name           = "dvdsub",

  727.     .long_name      = NULL_IF_CONFIG_SMALL("DVD subtitles"),

  728.     .type           = AVMEDIA_TYPE_SUBTITLE,

  729.     .id             = AV_CODEC_ID_DVD_SUBTITLE,

  730.     .priv_data_size = sizeof(DVDSubContext),

  731.     .init           = dvdsub_init,

  732.     .decode         = dvdsub_decode,

  733.     .close          = dvdsub_close,

  734.     .priv_class     = &dvdsub_class,

  735. };