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Diffstat (limited to 'contrib/ffmpeg/libavcodec/dvdsubdec.c')
-rw-r--r--contrib/ffmpeg/libavcodec/dvdsubdec.c509
1 files changed, 509 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavcodec/dvdsubdec.c b/contrib/ffmpeg/libavcodec/dvdsubdec.c
new file mode 100644
index 000000000..0927b7a17
--- /dev/null
+++ b/contrib/ffmpeg/libavcodec/dvdsubdec.c
@@ -0,0 +1,509 @@
+/*
+ * DVD subtitle decoding for ffmpeg
+ * Copyright (c) 2005 Fabrice Bellard.
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include "avcodec.h"
+#include "bitstream.h"
+#include "colorspace.h"
+#include "dsputil.h"
+
+//#define DEBUG
+
+static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
+{
+ uint8_t *cm = ff_cropTbl + MAX_NEG_CROP;
+ uint8_t r, g, b;
+ int i, y, cb, cr;
+ int r_add, g_add, b_add;
+
+ for (i = num_values; i > 0; i--) {
+ y = *ycbcr++;
+ cb = *ycbcr++;
+ cr = *ycbcr++;
+ YUV_TO_RGB1_CCIR(cb, cr);
+ YUV_TO_RGB2_CCIR(r, g, b, y);
+ *rgba++ = (*alpha++ << 24) | (r << 16) | (g << 8) | b;
+ }
+}
+
+static int decode_run_2bit(GetBitContext *gb, int *color)
+{
+ unsigned int v, t;
+
+ v = 0;
+ for (t = 1; v < t && t <= 0x40; t <<= 2)
+ v = (v << 4) | get_bits(gb, 4);
+ *color = v & 3;
+ if (v < 4) { /* Code for fill rest of line */
+ return INT_MAX;
+ }
+ return v >> 2;
+}
+
+static int decode_run_8bit(GetBitContext *gb, int *color)
+{
+ int len;
+ int has_run = get_bits1(gb);
+ if (get_bits1(gb))
+ *color = get_bits(gb, 8);
+ else
+ *color = get_bits(gb, 2);
+ if (has_run) {
+ if (get_bits1(gb)) {
+ len = get_bits(gb, 7);
+ if (len == 0)
+ len = INT_MAX;
+ else
+ len += 9;
+ } else
+ len = get_bits(gb, 3) + 2;
+ } else
+ len = 1;
+ return len;
+}
+
+static int decode_rle(uint8_t *bitmap, int linesize, int w, int h,
+ const uint8_t *buf, int start, int buf_size, int is_8bit)
+{
+ GetBitContext gb;
+ int bit_len;
+ int x, y, len, color;
+ uint8_t *d;
+
+ bit_len = (buf_size - start) * 8;
+ init_get_bits(&gb, buf + start, bit_len);
+
+ x = 0;
+ y = 0;
+ d = bitmap;
+ for(;;) {
+ if (get_bits_count(&gb) > bit_len)
+ return -1;
+ if (is_8bit)
+ len = decode_run_8bit(&gb, &color);
+ else
+ len = decode_run_2bit(&gb, &color);
+ len = FFMIN(len, w - x);
+ memset(d + x, color, len);
+ x += len;
+ if (x >= w) {
+ y++;
+ if (y >= h)
+ break;
+ d += linesize;
+ x = 0;
+ /* byte align */
+ align_get_bits(&gb);
+ }
+ }
+ return 0;
+}
+
+static void guess_palette(uint32_t *rgba_palette,
+ uint8_t *colormap,
+ uint8_t *alpha,
+ uint32_t subtitle_color)
+{
+ uint8_t color_used[16];
+ int nb_opaque_colors, i, level, j, r, g, b;
+
+ for(i = 0; i < 4; i++)
+ rgba_palette[i] = 0;
+
+ memset(color_used, 0, 16);
+ nb_opaque_colors = 0;
+ for(i = 0; i < 4; i++) {
+ if (alpha[i] != 0 && !color_used[colormap[i]]) {
+ color_used[colormap[i]] = 1;
+ nb_opaque_colors++;
+ }
+ }
+
+ if (nb_opaque_colors == 0)
+ return;
+
+ j = nb_opaque_colors;
+ memset(color_used, 0, 16);
+ for(i = 0; i < 4; i++) {
+ if (alpha[i] != 0) {
+ if (!color_used[colormap[i]]) {
+ level = (0xff * j) / nb_opaque_colors;
+ r = (((subtitle_color >> 16) & 0xff) * level) >> 8;
+ g = (((subtitle_color >> 8) & 0xff) * level) >> 8;
+ b = (((subtitle_color >> 0) & 0xff) * level) >> 8;
+ rgba_palette[i] = b | (g << 8) | (r << 16) | ((alpha[i] * 17) << 24);
+ color_used[colormap[i]] = (i + 1);
+ j--;
+ } else {
+ rgba_palette[i] = (rgba_palette[color_used[colormap[i]] - 1] & 0x00ffffff) |
+ ((alpha[i] * 17) << 24);
+ }
+ }
+ }
+}
+
+#define READ_OFFSET(a) (big_offsets ? AV_RB32(a) : AV_RB16(a))
+
+static int decode_dvd_subtitles(AVSubtitle *sub_header,
+ const uint8_t *buf, int buf_size)
+{
+ int cmd_pos, pos, cmd, x1, y1, x2, y2, offset1, offset2, next_cmd_pos;
+ int big_offsets, offset_size, is_8bit = 0;
+ const uint8_t *yuv_palette = 0;
+ uint8_t colormap[4], alpha[256];
+ int date;
+ int i;
+ int is_menu = 0;
+
+ if (buf_size < 10)
+ return -1;
+ sub_header->rects = NULL;
+ sub_header->num_rects = 0;
+ sub_header->start_display_time = 0;
+ sub_header->end_display_time = 0;
+
+ if (AV_RB16(buf) == 0) { /* HD subpicture with 4-byte offsets */
+ big_offsets = 1;
+ offset_size = 4;
+ cmd_pos = 6;
+ } else {
+ big_offsets = 0;
+ offset_size = 2;
+ cmd_pos = 2;
+ }
+
+ cmd_pos = READ_OFFSET(buf + cmd_pos);
+
+ while ((cmd_pos + 2 + offset_size) < buf_size) {
+ date = AV_RB16(buf + cmd_pos);
+ next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "cmd_pos=0x%04x next=0x%04x date=%d\n",
+ cmd_pos, next_cmd_pos, date);
+#endif
+ pos = cmd_pos + 2 + offset_size;
+ offset1 = -1;
+ offset2 = -1;
+ x1 = y1 = x2 = y2 = 0;
+ while (pos < buf_size) {
+ cmd = buf[pos++];
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "cmd=%02x\n", cmd);
+#endif
+ switch(cmd) {
+ case 0x00:
+ /* menu subpicture */
+ is_menu = 1;
+ break;
+ case 0x01:
+ /* set start date */
+ sub_header->start_display_time = (date << 10) / 90;
+ break;
+ case 0x02:
+ /* set end date */
+ sub_header->end_display_time = (date << 10) / 90;
+ break;
+ case 0x03:
+ /* set colormap */
+ if ((buf_size - pos) < 2)
+ goto fail;
+ colormap[3] = buf[pos] >> 4;
+ colormap[2] = buf[pos] & 0x0f;
+ colormap[1] = buf[pos + 1] >> 4;
+ colormap[0] = buf[pos + 1] & 0x0f;
+ pos += 2;
+ break;
+ case 0x04:
+ /* set alpha */
+ if ((buf_size - pos) < 2)
+ goto fail;
+ alpha[3] = buf[pos] >> 4;
+ alpha[2] = buf[pos] & 0x0f;
+ alpha[1] = buf[pos + 1] >> 4;
+ alpha[0] = buf[pos + 1] & 0x0f;
+ pos += 2;
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
+#endif
+ break;
+ case 0x05:
+ case 0x85:
+ if ((buf_size - pos) < 6)
+ goto fail;
+ x1 = (buf[pos] << 4) | (buf[pos + 1] >> 4);
+ x2 = ((buf[pos + 1] & 0x0f) << 8) | buf[pos + 2];
+ y1 = (buf[pos + 3] << 4) | (buf[pos + 4] >> 4);
+ y2 = ((buf[pos + 4] & 0x0f) << 8) | buf[pos + 5];
+ if (cmd & 0x80)
+ is_8bit = 1;
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "x1=%d x2=%d y1=%d y2=%d\n",
+ x1, x2, y1, y2);
+#endif
+ pos += 6;
+ break;
+ case 0x06:
+ if ((buf_size - pos) < 4)
+ goto fail;
+ offset1 = AV_RB16(buf + pos);
+ offset2 = AV_RB16(buf + pos + 2);
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
+#endif
+ pos += 4;
+ break;
+ case 0x86:
+ if ((buf_size - pos) < 8)
+ goto fail;
+ offset1 = AV_RB32(buf + pos);
+ offset2 = AV_RB32(buf + pos + 4);
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
+#endif
+ pos += 8;
+ break;
+
+ case 0x83:
+ /* HD set palette */
+ if ((buf_size - pos) < 768)
+ goto fail;
+ yuv_palette = buf + pos;
+ pos += 768;
+ break;
+ case 0x84:
+ /* HD set contrast (alpha) */
+ if ((buf_size - pos) < 256)
+ goto fail;
+ for (i = 0; i < 256; i++)
+ alpha[i] = 0xFF - buf[pos+i];
+ pos += 256;
+ break;
+
+ case 0xff:
+ goto the_end;
+ default:
+#ifdef DEBUG
+ av_log(NULL, AV_LOG_INFO, "unrecognised subpicture command 0x%x\n", cmd);
+#endif
+ goto the_end;
+ }
+ }
+ the_end:
+ if (offset1 >= 0) {
+ int w, h;
+ uint8_t *bitmap;
+
+ /* decode the bitmap */
+ w = x2 - x1 + 1;
+ if (w < 0)
+ w = 0;
+ h = y2 - y1;
+ if (h < 0)
+ h = 0;
+ if (w > 0 && h > 0) {
+ if (sub_header->rects != NULL) {
+ for (i = 0; i < sub_header->num_rects; i++) {
+ av_free(sub_header->rects[i].bitmap);
+ av_free(sub_header->rects[i].rgba_palette);
+ }
+ av_freep(&sub_header->rects);
+ sub_header->num_rects = 0;
+ }
+
+ bitmap = av_malloc(w * h);
+ sub_header->rects = av_mallocz(sizeof(AVSubtitleRect));
+ sub_header->num_rects = 1;
+ sub_header->rects[0].bitmap = bitmap;
+ decode_rle(bitmap, w * 2, w, (h + 1) / 2,
+ buf, offset1, buf_size, is_8bit);
+ decode_rle(bitmap + w, w * 2, w, h / 2,
+ buf, offset2, buf_size, is_8bit);
+ if (is_8bit) {
+ if (yuv_palette == 0)
+ goto fail;
+ sub_header->rects[0].rgba_palette = av_malloc(256 * 4);
+ sub_header->rects[0].nb_colors = 256;
+ yuv_a_to_rgba(yuv_palette, alpha, sub_header->rects[0].rgba_palette, 256);
+ } else {
+ sub_header->rects[0].rgba_palette = av_malloc(4 * 4);
+ sub_header->rects[0].nb_colors = 4;
+ guess_palette(sub_header->rects[0].rgba_palette,
+ colormap, alpha, 0xffff00);
+ }
+ sub_header->rects[0].x = x1;
+ sub_header->rects[0].y = y1;
+ sub_header->rects[0].w = w;
+ sub_header->rects[0].h = h;
+ sub_header->rects[0].linesize = w;
+ }
+ }
+ if (next_cmd_pos == cmd_pos)
+ break;
+ cmd_pos = next_cmd_pos;
+ }
+ if (sub_header->num_rects > 0)
+ return is_menu;
+ fail:
+ if (sub_header->rects != NULL) {
+ for (i = 0; i < sub_header->num_rects; i++) {
+ av_free(sub_header->rects[i].bitmap);
+ av_free(sub_header->rects[i].rgba_palette);
+ }
+ av_freep(&sub_header->rects);
+ sub_header->num_rects = 0;
+ }
+ return -1;
+}
+
+static int is_transp(const uint8_t *buf, int pitch, int n,
+ const uint8_t *transp_color)
+{
+ int i;
+ for(i = 0; i < n; i++) {
+ if (!transp_color[*buf])
+ return 0;
+ buf += pitch;
+ }
+ return 1;
+}
+
+/* return 0 if empty rectangle, 1 if non empty */
+static int find_smallest_bounding_rectangle(AVSubtitle *s)
+{
+ uint8_t transp_color[256];
+ int y1, y2, x1, x2, y, w, h, i;
+ uint8_t *bitmap;
+
+ if (s->num_rects == 0 || s->rects == NULL || s->rects[0].w <= 0 || s->rects[0].h <= 0)
+ return 0;
+
+ memset(transp_color, 0, 256);
+ for(i = 0; i < s->rects[0].nb_colors; i++) {
+ if ((s->rects[0].rgba_palette[i] >> 24) == 0)
+ transp_color[i] = 1;
+ }
+ y1 = 0;
+ while (y1 < s->rects[0].h && is_transp(s->rects[0].bitmap + y1 * s->rects[0].linesize,
+ 1, s->rects[0].w, transp_color))
+ y1++;
+ if (y1 == s->rects[0].h) {
+ av_freep(&s->rects[0].bitmap);
+ s->rects[0].w = s->rects[0].h = 0;
+ return 0;
+ }
+
+ y2 = s->rects[0].h - 1;
+ while (y2 > 0 && is_transp(s->rects[0].bitmap + y2 * s->rects[0].linesize, 1,
+ s->rects[0].w, transp_color))
+ y2--;
+ x1 = 0;
+ while (x1 < (s->rects[0].w - 1) && is_transp(s->rects[0].bitmap + x1, s->rects[0].linesize,
+ s->rects[0].h, transp_color))
+ x1++;
+ x2 = s->rects[0].w - 1;
+ while (x2 > 0 && is_transp(s->rects[0].bitmap + x2, s->rects[0].linesize, s->rects[0].h,
+ transp_color))
+ x2--;
+ w = x2 - x1 + 1;
+ h = y2 - y1 + 1;
+ bitmap = av_malloc(w * h);
+ if (!bitmap)
+ return 1;
+ for(y = 0; y < h; y++) {
+ memcpy(bitmap + w * y, s->rects[0].bitmap + x1 + (y1 + y) * s->rects[0].linesize, w);
+ }
+ av_freep(&s->rects[0].bitmap);
+ s->rects[0].bitmap = bitmap;
+ s->rects[0].linesize = w;
+ s->rects[0].w = w;
+ s->rects[0].h = h;
+ s->rects[0].x += x1;
+ s->rects[0].y += y1;
+ return 1;
+}
+
+#ifdef DEBUG
+#undef fprintf
+static void ppm_save(const char *filename, uint8_t *bitmap, int w, int h,
+ uint32_t *rgba_palette)
+{
+ int x, y, v;
+ FILE *f;
+
+ f = fopen(filename, "w");
+ if (!f) {
+ perror(filename);
+ exit(1);
+ }
+ fprintf(f, "P6\n"
+ "%d %d\n"
+ "%d\n",
+ w, h, 255);
+ for(y = 0; y < h; y++) {
+ for(x = 0; x < w; x++) {
+ v = rgba_palette[bitmap[y * w + x]];
+ putc((v >> 16) & 0xff, f);
+ putc((v >> 8) & 0xff, f);
+ putc((v >> 0) & 0xff, f);
+ }
+ }
+ fclose(f);
+}
+#endif
+
+static int dvdsub_decode(AVCodecContext *avctx,
+ void *data, int *data_size,
+ const uint8_t *buf, int buf_size)
+{
+ AVSubtitle *sub = (void *)data;
+ int is_menu;
+
+ is_menu = decode_dvd_subtitles(sub, buf, buf_size);
+
+ if (is_menu < 0) {
+ no_subtitle:
+ *data_size = 0;
+
+ return buf_size;
+ }
+ if (!is_menu && find_smallest_bounding_rectangle(sub) == 0)
+ goto no_subtitle;
+
+#if defined(DEBUG)
+ av_log(NULL, AV_LOG_INFO, "start=%d ms end =%d ms\n",
+ sub->start_display_time,
+ sub->end_display_time);
+ ppm_save("/tmp/a.ppm", sub->rects[0].bitmap,
+ sub->rects[0].w, sub->rects[0].h, sub->rects[0].rgba_palette);
+#endif
+
+ *data_size = 1;
+ return buf_size;
+}
+
+AVCodec dvdsub_decoder = {
+ "dvdsub",
+ CODEC_TYPE_SUBTITLE,
+ CODEC_ID_DVD_SUBTITLE,
+ 0,
+ NULL,
+ NULL,
+ NULL,
+ dvdsub_decode,
+};
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