mirror of https://git.ffmpeg.org/ffmpeg.git
561 lines
17 KiB
C
561 lines
17 KiB
C
/*
|
|
* DVD subtitle decoding
|
|
* Copyright (c) 2005 Fabrice Bellard
|
|
*
|
|
* This file is part of Libav.
|
|
*
|
|
* Libav 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.
|
|
*
|
|
* Libav 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 Libav; if not, write to the Free Software
|
|
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
|
|
*/
|
|
|
|
#include "avcodec.h"
|
|
#include "get_bits.h"
|
|
#include "internal.h"
|
|
|
|
#include "libavutil/attributes.h"
|
|
#include "libavutil/colorspace.h"
|
|
#include "libavutil/imgutils.h"
|
|
#include "libavutil/avstring.h"
|
|
|
|
typedef struct DVDSubContext {
|
|
uint32_t palette[16];
|
|
int has_palette;
|
|
} DVDSubContext;
|
|
|
|
static void yuv_a_to_rgba(const uint8_t *ycbcr, const uint8_t *alpha, uint32_t *rgba, int num_values)
|
|
{
|
|
const uint8_t *cm = ff_crop_tab + 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++;
|
|
cr = *ycbcr++;
|
|
cb = *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(DVDSubContext* ctx,
|
|
uint32_t *rgba_palette,
|
|
uint8_t *colormap,
|
|
uint8_t *alpha,
|
|
uint32_t subtitle_color)
|
|
{
|
|
uint8_t color_used[16] = { 0 };
|
|
int nb_opaque_colors, i, level, j, r, g, b;
|
|
|
|
if (ctx->has_palette) {
|
|
for (i = 0; i < 4; i++)
|
|
rgba_palette[i] = (ctx->palette[colormap[i]] & 0x00ffffff)
|
|
| ((alpha[i] * 17) << 24);
|
|
return;
|
|
}
|
|
|
|
for(i = 0; i < 4; i++)
|
|
rgba_palette[i] = 0;
|
|
|
|
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(DVDSubContext *ctx, 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] = { 0 }, alpha[256] = { 0 };
|
|
int date;
|
|
int i;
|
|
int is_menu = 0;
|
|
|
|
if (buf_size < 10)
|
|
return -1;
|
|
memset(sub_header, 0, sizeof(*sub_header));
|
|
|
|
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 > 0 && cmd_pos < buf_size - 2 - offset_size) {
|
|
date = AV_RB16(buf + cmd_pos);
|
|
next_cmd_pos = READ_OFFSET(buf + cmd_pos + 2);
|
|
ff_dlog(NULL, "cmd_pos=0x%04x next=0x%04x date=%d\n",
|
|
cmd_pos, next_cmd_pos, date);
|
|
pos = cmd_pos + 2 + offset_size;
|
|
offset1 = -1;
|
|
offset2 = -1;
|
|
x1 = y1 = x2 = y2 = 0;
|
|
while (pos < buf_size) {
|
|
cmd = buf[pos++];
|
|
ff_dlog(NULL, "cmd=%02x\n", cmd);
|
|
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;
|
|
ff_dlog(NULL, "alpha=%x%x%x%x\n", alpha[0],alpha[1],alpha[2],alpha[3]);
|
|
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;
|
|
ff_dlog(NULL, "x1=%d x2=%d y1=%d y2=%d\n", x1, x2, y1, y2);
|
|
pos += 6;
|
|
break;
|
|
case 0x06:
|
|
if ((buf_size - pos) < 4)
|
|
goto fail;
|
|
offset1 = AV_RB16(buf + pos);
|
|
offset2 = AV_RB16(buf + pos + 2);
|
|
ff_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
|
|
pos += 4;
|
|
break;
|
|
case 0x86:
|
|
if ((buf_size - pos) < 8)
|
|
goto fail;
|
|
offset1 = AV_RB32(buf + pos);
|
|
offset2 = AV_RB32(buf + pos + 4);
|
|
ff_dlog(NULL, "offset1=0x%04x offset2=0x%04x\n", offset1, offset2);
|
|
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:
|
|
ff_dlog(NULL, "unrecognised subpicture command 0x%x\n", cmd);
|
|
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) {
|
|
for (i = 0; i < sub_header->num_rects; i++) {
|
|
av_freep(&sub_header->rects[i]->pict.data[0]);
|
|
av_freep(&sub_header->rects[i]->pict.data[1]);
|
|
av_freep(&sub_header->rects[i]);
|
|
}
|
|
av_freep(&sub_header->rects);
|
|
sub_header->num_rects = 0;
|
|
}
|
|
|
|
sub_header->rects = av_mallocz(sizeof(*sub_header->rects));
|
|
if (!sub_header->rects)
|
|
goto fail;
|
|
sub_header->rects[0] = av_mallocz(sizeof(AVSubtitleRect));
|
|
if (!sub_header->rects[0])
|
|
goto fail;
|
|
sub_header->num_rects = 1;
|
|
bitmap = sub_header->rects[0]->pict.data[0] = av_malloc(w * h);
|
|
if (!bitmap)
|
|
goto fail;
|
|
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);
|
|
sub_header->rects[0]->pict.data[1] = av_mallocz(AVPALETTE_SIZE);
|
|
if (!sub_header->rects[0]->pict.data[1])
|
|
goto fail;
|
|
if (is_8bit) {
|
|
if (yuv_palette == 0)
|
|
goto fail;
|
|
sub_header->rects[0]->nb_colors = 256;
|
|
yuv_a_to_rgba(yuv_palette, alpha, (uint32_t*)sub_header->rects[0]->pict.data[1], 256);
|
|
} else {
|
|
sub_header->rects[0]->nb_colors = 4;
|
|
guess_palette(ctx,
|
|
(uint32_t*)sub_header->rects[0]->pict.data[1],
|
|
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]->type = SUBTITLE_BITMAP;
|
|
sub_header->rects[0]->pict.linesize[0] = 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) {
|
|
for (i = 0; i < sub_header->num_rects; i++) {
|
|
av_freep(&sub_header->rects[i]->pict.data[0]);
|
|
av_freep(&sub_header->rects[i]->pict.data[1]);
|
|
av_freep(&sub_header->rects[i]);
|
|
}
|
|
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] = { 0 };
|
|
int y1, y2, x1, x2, y, w, h, i;
|
|
uint8_t *bitmap;
|
|
|
|
if (s->num_rects == 0 || !s->rects || s->rects[0]->w <= 0 || s->rects[0]->h <= 0)
|
|
return 0;
|
|
|
|
for(i = 0; i < s->rects[0]->nb_colors; i++) {
|
|
if ((((uint32_t*)s->rects[0]->pict.data[1])[i] >> 24) == 0)
|
|
transp_color[i] = 1;
|
|
}
|
|
y1 = 0;
|
|
while (y1 < s->rects[0]->h && is_transp(s->rects[0]->pict.data[0] + y1 * s->rects[0]->pict.linesize[0],
|
|
1, s->rects[0]->w, transp_color))
|
|
y1++;
|
|
if (y1 == s->rects[0]->h) {
|
|
av_freep(&s->rects[0]->pict.data[0]);
|
|
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]->pict.data[0] + y2 * s->rects[0]->pict.linesize[0], 1,
|
|
s->rects[0]->w, transp_color))
|
|
y2--;
|
|
x1 = 0;
|
|
while (x1 < (s->rects[0]->w - 1) && is_transp(s->rects[0]->pict.data[0] + x1, s->rects[0]->pict.linesize[0],
|
|
s->rects[0]->h, transp_color))
|
|
x1++;
|
|
x2 = s->rects[0]->w - 1;
|
|
while (x2 > 0 && is_transp(s->rects[0]->pict.data[0] + x2, s->rects[0]->pict.linesize[0], 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]->pict.data[0] + x1 + (y1 + y) * s->rects[0]->pict.linesize[0], w);
|
|
}
|
|
av_freep(&s->rects[0]->pict.data[0]);
|
|
s->rects[0]->pict.data[0] = bitmap;
|
|
s->rects[0]->pict.linesize[0] = 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
|
|
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,
|
|
AVPacket *avpkt)
|
|
{
|
|
DVDSubContext *ctx = avctx->priv_data;
|
|
const uint8_t *buf = avpkt->data;
|
|
int buf_size = avpkt->size;
|
|
AVSubtitle *sub = data;
|
|
int is_menu;
|
|
|
|
is_menu = decode_dvd_subtitles(ctx, 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)
|
|
ff_dlog(NULL, "start=%d ms end =%d ms\n",
|
|
sub->start_display_time,
|
|
sub->end_display_time);
|
|
ppm_save("/tmp/a.ppm", sub->rects[0]->pict.data[0],
|
|
sub->rects[0]->w, sub->rects[0]->h, sub->rects[0]->pict.data[1]);
|
|
#endif
|
|
|
|
*data_size = 1;
|
|
return buf_size;
|
|
}
|
|
|
|
static av_cold int dvdsub_init(AVCodecContext *avctx)
|
|
{
|
|
DVDSubContext *ctx = avctx->priv_data;
|
|
char *data, *cur;
|
|
int ret = 0;
|
|
|
|
if (!avctx->extradata || !avctx->extradata_size)
|
|
return 0;
|
|
|
|
data = av_malloc(avctx->extradata_size + 1);
|
|
if (!data)
|
|
return AVERROR(ENOMEM);
|
|
memcpy(data, avctx->extradata, avctx->extradata_size);
|
|
data[avctx->extradata_size] = '\0';
|
|
cur = data;
|
|
|
|
while (*cur) {
|
|
if (strncmp("palette:", cur, 8) == 0) {
|
|
int i;
|
|
char *p = cur + 8;
|
|
ctx->has_palette = 1;
|
|
for (i = 0; i < 16; i++) {
|
|
ctx->palette[i] = strtoul(p, &p, 16);
|
|
while (*p == ',' || av_isspace(*p))
|
|
p++;
|
|
}
|
|
} else if (!strncmp("size:", cur, 5)) {
|
|
int w, h;
|
|
if (sscanf(cur + 5, "%dx%d", &w, &h) == 2) {
|
|
ret = ff_set_dimensions(avctx, w, h);
|
|
if (ret < 0)
|
|
goto fail;
|
|
}
|
|
}
|
|
cur += strcspn(cur, "\n\r");
|
|
cur += strspn(cur, "\n\r");
|
|
}
|
|
|
|
fail:
|
|
av_free(data);
|
|
return ret;
|
|
}
|
|
|
|
AVCodec ff_dvdsub_decoder = {
|
|
.name = "dvdsub",
|
|
.long_name = NULL_IF_CONFIG_SMALL("DVD subtitles"),
|
|
.type = AVMEDIA_TYPE_SUBTITLE,
|
|
.id = AV_CODEC_ID_DVD_SUBTITLE,
|
|
.priv_data_size = sizeof(DVDSubContext),
|
|
.init = dvdsub_init,
|
|
.decode = dvdsub_decode,
|
|
};
|