Commit af469427 authored by Juanjo's avatar Juanjo
Browse files

- Fix pts calculation on mpeg mux (A/V sync) - Thanks to Lennert Buytenhek

- Fix temporal-reference-glitches for MPEG1 - Thanks to Lennert Buytenhek

Originally committed as revision 343 to svn://svn.ffmpeg.org/ffmpeg/trunk
parent ce7c56c2
......@@ -14,7 +14,6 @@ Planned in next release:
- find a solution to clear feed1.ffm if format change.
- new grab architecture : use avformat instead of audio: and video:
protocol.
- correct PTS handling to sync audio and video.
- fix 0 size picture in AVIs = skip picture
BUGS:
......
......@@ -17,6 +17,7 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "avformat.h"
#include "tick.h"
#define MAX_PAYLOAD_SIZE 4096
#define NB_STREAMS 2
......@@ -27,7 +28,8 @@ typedef struct {
UINT8 id;
int max_buffer_size; /* in bytes */
int packet_number;
float pts;
INT64 pts;
Ticker pts_ticker;
INT64 start_pts;
} StreamInfo;
......@@ -211,6 +213,20 @@ static int mpeg_mux_init(AVFormatContext *ctx)
stream->packet_number = 0;
stream->pts = 0;
stream->start_pts = -1;
st = ctx->streams[i];
switch (st->codec.codec_type) {
case CODEC_TYPE_AUDIO:
ticker_init(&stream->pts_ticker,
st->codec.sample_rate,
90000 * st->codec.frame_size);
break;
case CODEC_TYPE_VIDEO:
ticker_init(&stream->pts_ticker,
st->codec.frame_rate,
90000 * FRAME_RATE_BASE);
break;
}
}
return 0;
fail:
......@@ -316,7 +332,7 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx,
while (size > 0) {
/* set pts */
if (stream->start_pts == -1)
stream->start_pts = stream->pts * 90000.0;
stream->start_pts = stream->pts;
len = s->packet_data_max_size - stream->buffer_ptr;
if (len > size)
len = size;
......@@ -327,16 +343,12 @@ static int mpeg_mux_write_packet(AVFormatContext *ctx,
while (stream->buffer_ptr >= s->packet_data_max_size) {
/* output the packet */
if (stream->start_pts == -1)
stream->start_pts = stream->pts * 90000.0;
stream->start_pts = stream->pts;
flush_packet(ctx, stream_index);
}
}
if (st->codec.codec_type == CODEC_TYPE_AUDIO) {
stream->pts += (float)st->codec.frame_size / st->codec.sample_rate;
} else {
stream->pts += FRAME_RATE_BASE / (float)st->codec.frame_rate;
}
stream->pts += ticker_tick(&stream->pts_ticker, 1);
return 0;
}
......
/* tick.h - Compute successive integer multiples of a rational
* number without long-term rounding error.
* (c)2002 by Lennert Buytenhek <buytenh@gnu.org>
* File licensed under the GPL, see http://www.fsf.org/ for more info.
* Dedicated to Marija Kulikova.
*/
#include "avcodec.h"
typedef struct Ticker {
int value;
int inrate;
int outrate;
int div;
int mod;
} Ticker;
extern void ticker_init(Ticker *tick, INT64 inrate, INT64 outrate);
extern inline int ticker_tick(Ticker *tick, int num)
{
int n = num * tick->div;
tick->value += num * tick->mod;
while (tick->value > 0) {
tick->value -= tick->inrate;
n++;
}
return n;
}
......@@ -17,6 +17,7 @@
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "avformat.h"
#include "tick.h"
#ifndef CONFIG_WIN32
#include <unistd.h>
#include <fcntl.h>
......@@ -615,4 +616,31 @@ int get_frame_filename(char *buf, int buf_size,
return -1;
}
static int gcd(INT64 a, INT64 b)
{
INT64 c;
while (1) {
c = a % b;
if (c == 0)
return b;
a = b;
b = c;
}
}
void ticker_init(Ticker *tick, INT64 inrate, INT64 outrate)
{
int g;
g = gcd(inrate, outrate);
inrate /= g;
outrate /= g;
tick->value = -outrate/2;
tick->inrate = inrate;
tick->outrate = outrate;
tick->div = tick->outrate / tick->inrate;
tick->mod = tick->outrate % tick->inrate;
}
......@@ -129,7 +129,6 @@ static void mpeg1_encode_sequence_header(MpegEncContext *s)
}
}
s->fake_picture_number++;
}
......@@ -226,6 +225,7 @@ void mpeg1_encode_picture_header(MpegEncContext *s, int picture_number)
/* temporal reference */
put_bits(&s->pb, 10, (s->fake_picture_number -
s->gop_picture_number) & 0x3ff);
s->fake_picture_number++;
put_bits(&s->pb, 3, s->pict_type);
put_bits(&s->pb, 16, 0xffff); /* non constant bit rate */
......
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