generic-library/ffmpeg
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

use libavformats index system instead of the half duplicated mess in avidec.c

Browse Source 
Originally committed as revision 4036 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2005-03-13 02:04:35 +00:00
parent 7071e56799
commit 52a0bbff1f
1 changed files with 61 additions and 128 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

189
libavformat/avidec.c
View File

@ -20,19 +20,13 @@
#include "avi.h"
#include "dv.h"
#undef NDEBUG
#include <assert.h>
//#define DEBUG
//#define DEBUG_SEEK
typedef struct AVIIndexEntry {
unsigned int flags;
unsigned int pos;
unsigned int cum_len; /* sum of all lengths before this packet */
} AVIIndexEntry;
typedef struct AVIStream {
AVIIndexEntry *index_entries;
int nb_index_entries;
int index_entries_allocated_size;
int frame_offset; /* current frame (video) or byte (audio) counter
(used to compute the pts) */
int scale;
@ -40,7 +34,6 @@ typedef struct AVIStream {
int sample_size; /* audio only data */
int start;
int new_frame_offset; /* temporary storage (used during seek) */
int cum_len; /* temporary storage (used during seek) */
int prefix; ///< normally 'd'<<8 + 'c' or 'w'<<8 + 'b'
@ -488,11 +481,19 @@ resync:
pkt->dts /= ast->sample_size;
//av_log(NULL, AV_LOG_DEBUG, "dts:%Ld offset:%d %d/%d smpl_siz:%d base:%d st:%d size:%d\n", pkt->dts, ast->frame_offset, ast->scale, ast->rate, ast->sample_size, AV_TIME_BASE, n, size);
pkt->stream_index = n;
/* FIXME: We really should read index for that */
if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
if (ast->frame_offset < ast->nb_index_entries) {
if (ast->index_entries[ast->frame_offset].flags & AVIIF_INDEX)
pkt->flags |= PKT_FLAG_KEY;
if(st->index_entries){
AVIndexEntry *e;
int index;
index= av_index_search_timestamp(st, pkt->dts, 0);
e= &st->index_entries[index];
if(e->timestamp == ast->frame_offset){
if (e->flags & AVINDEX_KEYFRAME)
pkt->flags |= PKT_FLAG_KEY;
}
} else {
/* if no index, better to say that all frames
are key frames */
@ -551,14 +552,11 @@ static int avi_read_idx1(AVFormatContext *s, int size)
int nb_index_entries, i;
AVStream *st;
AVIStream *ast;
AVIIndexEntry *ie, *entries;
unsigned int index, tag, flags, pos, len;
nb_index_entries = size / 16;
if (nb_index_entries <= 0)
return -1;
if(nb_index_entries + 1 >= UINT_MAX / sizeof(AVIIndexEntry))
return -1;
/* read the entries and sort them in each stream component */
for(i = 0; i < nb_index_entries; i++) {
@ -566,8 +564,8 @@ static int avi_read_idx1(AVFormatContext *s, int size)
flags = get_le32(pb);
pos = get_le32(pb);
len = get_le32(pb);
#if defined(DEBUG_SEEK) && 0
printf("%d: tag=0x%x flags=0x%x pos=0x%x len=%d\n",
#if defined(DEBUG_SEEK)
av_log(NULL, AV_LOG_DEBUG, "%d: tag=0x%x flags=0x%x pos=0x%x len=%d/",
i, tag, flags, pos, len);
#endif
index = ((tag & 0xff) - '0') * 10;
@ -577,18 +575,15 @@ static int avi_read_idx1(AVFormatContext *s, int size)
st = s->streams[index];
ast = st->priv_data;
entries = av_fast_realloc(ast->index_entries,
&ast->index_entries_allocated_size,
(ast->nb_index_entries + 1) *
sizeof(AVIIndexEntry));
if (entries) {
ast->index_entries = entries;
ie = &entries[ast->nb_index_entries++];
ie->flags = flags;
ie->pos = pos;
ie->cum_len = ast->cum_len;
ast->cum_len += len;
}
if(ast->sample_size)
len /= ast->sample_size;
else
len = 1;
#if defined(DEBUG_SEEK)
av_log(NULL, AV_LOG_DEBUG, "%d cum_len=%d\n", len, ast->cum_len);
#endif
av_add_index_entry(st, pos, ast->cum_len, 0, (flags&AVIIF_INDEX) ? AVINDEX_KEYFRAME : 0);
ast->cum_len += len;
}
return 0;
}
@ -636,38 +631,11 @@ static int avi_load_index(AVFormatContext *s)
return 0;
}
/* return the index entry whose position is immediately >= 'wanted_pos' */
static int locate_frame_in_index(AVIIndexEntry *entries,
int nb_entries, int wanted_pos)
{
int a, b, m, pos;
a = 0;
b = nb_entries - 1;
while (a <= b) {
m = (a + b) >> 1;
pos = entries[m].pos;
if (pos == wanted_pos)
goto found;
else if (pos > wanted_pos) {
b = m - 1;
} else {
a = m + 1;
}
}
m = a;
if (m > 0)
m--;
found:
return m;
}
static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)
{
AVIContext *avi = s->priv_data;
AVStream *st;
AVIStream *ast;
int frame_number, i;
int i, index;
int64_t pos;
if (!avi->index_loaded) {
@ -675,79 +643,47 @@ static int avi_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp
avi_load_index(s);
avi->index_loaded = 1;
}
if (stream_index < 0) {
for(i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
if (st->codec.codec_type == CODEC_TYPE_VIDEO)
goto found;
}
return -1;
found:
stream_index = i;
}
assert(stream_index>= 0);
st = s->streams[stream_index];
if (st->codec.codec_type != CODEC_TYPE_VIDEO)
index= av_index_search_timestamp(st, timestamp, flags);
if(index<0)
return -1;
ast = st->priv_data;
/* compute the frame number */
frame_number = timestamp;
#ifdef DEBUG_SEEK
printf("timestamp=%0.3f nb_indexes=%d frame_number=%d\n",
(double)timestamp / AV_TIME_BASE,
ast->nb_index_entries, frame_number);
#endif
/* find a closest key frame before */
if (frame_number >= ast->nb_index_entries)
return -1;
while (frame_number >= 0 &&
!(ast->index_entries[frame_number].flags & AVIIF_INDEX))
frame_number--;
if (frame_number < 0)
return -1;
ast->new_frame_offset = frame_number;
/* find the position */
pos = ast->index_entries[frame_number].pos;
pos = st->index_entries[index].pos;
timestamp = st->index_entries[index].timestamp;
// av_log(NULL, AV_LOG_DEBUG, "XX %Ld %d %Ld\n", timestamp, index, st->index_entries[index].timestamp);
#ifdef DEBUG_SEEK
printf("key_frame_number=%d pos=0x%llx\n",
frame_number, pos);
#endif
/* update the frame counters for all the other stream by looking
at the positions just after the one found */
for(i = 0; i < s->nb_streams; i++) {
int j;
if (i != stream_index) {
st = s->streams[i];
ast = st->priv_data;
if (ast->nb_index_entries <= 0)
return -1;
j = locate_frame_in_index(ast->index_entries,
ast->nb_index_entries,
pos);
/* get next frame */
if ((j + 1) < ast->nb_index_entries)
j++;
/* extract the current frame number */
if (ast->sample_size==0)
ast->new_frame_offset = j;
else
ast->new_frame_offset = ast->index_entries[j].cum_len;
}
}
/* everything is OK now. We can update the frame offsets */
for(i = 0; i < s->nb_streams; i++) {
st = s->streams[i];
ast = st->priv_data;
ast->frame_offset = ast->new_frame_offset;
#ifdef DEBUG_SEEK
printf("%d: frame_offset=%d\n", i,
ast->frame_offset);
AVStream *st2 = s->streams[i];
AVIStream *ast2 = st2->priv_data;
if (st2->nb_index_entries <= 0)
continue;
// assert(st2->codec.block_align);
assert(st2->time_base.den == ast2->rate);
assert(st2->time_base.num == ast2->scale);
index = av_index_search_timestamp(
st2,
av_rescale(timestamp, st2->time_base.den*(int64_t)st->time_base.num, st->time_base.den * (int64_t)st2->time_base.num),
flags | AVSEEK_FLAG_BACKWARD);
if(index<0)
index=0;
#if 1
while(index>0 && st2->index_entries[index].pos > pos)
index--;
while(index+1 < st2->nb_index_entries && st2->index_entries[index].pos < pos)
index++;
#endif
// av_log(NULL, AV_LOG_DEBUG, "%Ld %d %Ld\n", timestamp, index, st2->index_entries[index].timestamp);
/* extract the current frame number */
ast2->frame_offset = st2->index_entries[index].timestamp;
if(ast2->sample_size)
ast2->frame_offset *=ast2->sample_size;
}
if (avi->dv_demux)
dv_flush_audio_packets(avi->dv_demux);
/* do the seek */
@ -764,10 +700,7 @@ static int avi_read_close(AVFormatContext *s)
for(i=0;i<s->nb_streams;i++) {
AVStream *st = s->streams[i];
AVIStream *ast = st->priv_data;
if(ast){
av_free(ast->index_entries);
av_free(ast);
}
av_free(ast);
av_free(st->codec.extradata);
av_free(st->codec.palctrl);
}