ffmpeg/libavcodec/vp9_parser.c
wm4 a83b6b077c vp9: assign PTS to visible instead of invisible frames
All the webm/vp9 files I have seen so far can have packets that contain
1 invisible and 1 visible frame. The vp9 parser separates them. Since
the invisible frame is always (?) the first sub-packet, the new packet
is assigned the PTS of the original packet, while the packet containing
the visible frame has no PTS.

This patch essentially reassigns the PTS from the invisible to the
visible frame.

Reviewed-by: "Ronald S. Bultje" <rsbultje@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
2015-02-05 21:16:26 +01:00

134 lines
3.9 KiB
C

/*
* Copyright (C) 2008 Michael Niedermayer
*
* 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 "libavutil/intreadwrite.h"
#include "parser.h"
typedef struct VP9ParseContext {
int n_frames; // 1-8
int size[8];
int64_t pts;
} VP9ParseContext;
static void parse_frame(AVCodecParserContext *ctx, const uint8_t *buf, int size)
{
VP9ParseContext *s = ctx->priv_data;
if (buf[0] & 0x4) {
ctx->pict_type = AV_PICTURE_TYPE_P;
ctx->key_frame = 0;
} else {
ctx->pict_type = AV_PICTURE_TYPE_I;
ctx->key_frame = 1;
}
if (buf[0] & 0x2) {
if (ctx->pts == AV_NOPTS_VALUE)
ctx->pts = s->pts;
s->pts = AV_NOPTS_VALUE;
} else {
s->pts = ctx->pts;
ctx->pts = AV_NOPTS_VALUE;
}
}
static int parse(AVCodecParserContext *ctx,
AVCodecContext *avctx,
const uint8_t **out_data, int *out_size,
const uint8_t *data, int size)
{
VP9ParseContext *s = ctx->priv_data;
int full_size = size;
int marker;
if (size <= 0) {
*out_size = 0;
*out_data = data;
return 0;
}
if (s->n_frames > 0) {
*out_data = data;
*out_size = s->size[--s->n_frames];
parse_frame(ctx, *out_data, *out_size);
return s->n_frames > 0 ? *out_size : size /* i.e. include idx tail */;
}
marker = data[size - 1];
if ((marker & 0xe0) == 0xc0) {
int nbytes = 1 + ((marker >> 3) & 0x3);
int n_frames = 1 + (marker & 0x7), idx_sz = 2 + n_frames * nbytes;
if (size >= idx_sz && data[size - idx_sz] == marker) {
const uint8_t *idx = data + size + 1 - idx_sz;
int first = 1;
switch (nbytes) {
#define case_n(a, rd) \
case a: \
while (n_frames--) { \
unsigned sz = rd; \
idx += a; \
if (sz > size) { \
s->n_frames = 0; \
*out_size = size; \
*out_data = data; \
av_log(avctx, AV_LOG_ERROR, \
"Superframe packet size too big: %u > %d\n", \
sz, size); \
return full_size; \
} \
if (first) { \
first = 0; \
*out_data = data; \
*out_size = sz; \
s->n_frames = n_frames; \
} else { \
s->size[n_frames] = sz; \
} \
data += sz; \
size -= sz; \
} \
parse_frame(ctx, *out_data, *out_size); \
return *out_size
case_n(1, *idx);
case_n(2, AV_RL16(idx));
case_n(3, AV_RL24(idx));
case_n(4, AV_RL32(idx));
}
}
}
*out_data = data;
*out_size = size;
parse_frame(ctx, data, size);
return size;
}
AVCodecParser ff_vp9_parser = {
.codec_ids = { AV_CODEC_ID_VP9 },
.priv_data_size = sizeof(VP9ParseContext),
.parser_parse = parse,
};