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Add HD-DVD subpicture decoding.

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Patch by: Ian Caulfield, ian caulfield & gmx at

Originally committed as revision 9788 to svn://svn.ffmpeg.org/ffmpeg/trunk
pull/126/head
Ian Caulfield 18 years ago committed by Panagiotis Issaris
parent a363effbdf
commit 1aadf63fd1
1 changed files with 143 additions and 36 deletions
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  1. 179
      libavcodec/dvdsubdec.c

179
libavcodec/dvdsubdec.c
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@ -19,50 +19,92 @@
* 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 dvdsub_init_decoder(AVCodecContext *avctx)
{
return 0;
}
static int get_nibble(const uint8_t *buf, int nibble_offset)
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)
{
return (buf[nibble_offset >> 1] >> ((1 - (nibble_offset & 1)) << 2)) & 0xf;
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 nibble_offset, int buf_size)
const uint8_t *buf, int start, int buf_size, int is_8bit)
{
unsigned int v;
int x, y, len, color, nibble_end;
GetBitContext gb;
int bit_len;
int x, y, len, color;
uint8_t *d;
nibble_end = buf_size * 2;
bit_len = (buf_size - start) * 8;
init_get_bits(&gb, buf + start, bit_len);
x = 0;
y = 0;
d = bitmap;
for(;;) {
if (nibble_offset >= nibble_end)
if (get_bits_count(&gb) > bit_len)
return -1;
v = get_nibble(buf, nibble_offset++);
if (v < 0x4) {
v = (v << 4) | get_nibble(buf, nibble_offset++);
if (v < 0x10) {
v = (v << 4) | get_nibble(buf, nibble_offset++);
if (v < 0x040) {
v = (v << 4) | get_nibble(buf, nibble_offset++);
if (v < 4) {
v |= (w - x) << 2;
}
}
}
}
len = v >> 2;
if (len > (w - x))
len = (w - x);
color = v & 0x03;
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) {
@ -72,7 +114,7 @@ static int decode_rle(uint8_t *bitmap, int linesize, int w, int h,
d += linesize;
x = 0;
/* byte align */
nibble_offset += (nibble_offset & 1);
align_get_bits(&gb);
}
}
return 0;
@ -121,31 +163,46 @@ static void guess_palette(uint32_t *rgba_palette,
}
}
#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;
uint8_t colormap[4], alpha[4];
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 < 4)
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;
cmd_pos = AV_RB16(buf + 2);
while ((cmd_pos + 4) < buf_size) {
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 = AV_RB16(buf + cmd_pos + 2);
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 + 4;
pos = cmd_pos + 2 + offset_size;
offset1 = -1;
offset2 = -1;
x1 = y1 = x2 = y2 = 0;
@ -191,12 +248,15 @@ static int decode_dvd_subtitles(AVSubtitle *sub_header,
#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);
@ -213,8 +273,39 @@ static int decode_dvd_subtitles(AVSubtitle *sub_header,
#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;
}
}
@ -243,20 +334,28 @@ static int decode_dvd_subtitles(AVSubtitle *sub_header,
bitmap = av_malloc(w * h);
sub_header->rects = av_mallocz(sizeof(AVSubtitleRect));
sub_header->num_rects = 1;
sub_header->rects[0].rgba_palette = av_malloc(4 * 4);
sub_header->rects[0].bitmap = bitmap;
decode_rle(bitmap, w * 2, w, (h + 1) / 2,
buf, offset1 * 2, buf_size);
buf, offset1, buf_size, is_8bit);
decode_rle(bitmap + w, w * 2, w, h / 2,
buf, offset2 * 2, buf_size);
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].nb_colors = 4;
sub_header->rects[0].linesize = w;
sub_header->rects[0].bitmap = bitmap;
}
}
if (next_cmd_pos == cmd_pos)
@ -266,6 +365,14 @@ static int decode_dvd_subtitles(AVSubtitle *sub_header,
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;
}

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