[FFmpeg-soc] [soc]: r5826 - in seek2010: . seek2010.patch

[Michael Niedermayer]

On Wed, Jun 09, 2010 at 03:42:09PM +0200, mchinen wrote:
> Author: mchinen
> Date: Wed Jun  9 15:42:08 2010
> New Revision: 5826
> 
> Log:
> creating seek2010 dir for my soc proj and adding current patch
[...]

> +Index: libavformat/avformat.h
> +===================================================================
> +--- libavformat/avformat.h	(revision 23548)
> ++++ libavformat/avformat.h	(working copy)
> +@@ -390,6 +390,21 @@
> +     int min_distance;         /**< Minimum distance between this and the previous keyframe, used to avoid unneeded searching. */
> + } AVIndexEntry;
> + 
> ++#define AV_SEEKTABLE_BUILDING   0x0001
> ++#define AV_SEEKTABLE_CBR        0x0002
> ++#define AV_SEEKTABLE_FINISHED   0x0004
> ++#define AV_SEEKTABLE_COPIED     0x0008

missing documentation 


[...]

> +@@ -531,6 +546,9 @@
> +      * Number of frames that have been demuxed during av_find_stream_info()
> +      */
> +     int codec_info_nb_frames;
> ++
> ++    /* new av_seek_frame() support */
> ++    AVSeekTable seek_table;
> + } AVStream;

we alraedy have a table for seeking, that is AVStream.index_entries
why do you add a second table?


[...]
> +Index: libavformat/utils.c
> +===================================================================
> +--- libavformat/utils.c	(revision 23548)
> ++++ libavformat/utils.c	(working copy)
> +@@ -1001,7 +1001,38 @@
> +         pkt->convergence_duration = pc->convergence_duration;
> + }
> + 
> ++static int av_add_table_entry(AVStream *st,
> ++                            int64_t pos, int64_t timestamp, int size, int distance, int flags)
> ++{
> ++    AVIndexEntry *entries, *ie;
> ++    int index;
> + 
> ++    if((unsigned)st->nb_index_entries + 1 >= UINT_MAX / sizeof(AVIndexEntry))
> ++        return -1;
> ++
> ++    entries = av_fast_realloc(st->seek_table.index_entries,
> ++                              &st->seek_table.index_entries_allocated_size,
> ++                              (st->seek_table.nb_index_entries + 1) *
> ++                              sizeof(AVIndexEntry));
> ++    if(!entries)
> ++        return -1;
> ++
> ++    st->seek_table.index_entries= entries;
> ++
> ++    /* we assume the indecies are placed in order */
> ++    ie = &st->seek_table.index_entries[st->seek_table.nb_index_entries++];
> ++    assert(index==0 || ie[-1].timestamp < timestamp);
> ++
> ++    ie->pos = pos;
> ++    ie->timestamp = timestamp;
> ++    ie->min_distance= distance;
> ++    ie->size= size;
> ++    ie->flags = flags;
> ++
> ++    return st->seek_table.nb_index_entries;
> ++}
> ++
> ++
> + static int av_read_frame_internal(AVFormatContext *s, AVPacket *pkt)
> + {
> +     AVStream *st;
> +@@ -1359,6 +1390,7 @@
> +     int a, b, m;
> +     int64_t timestamp;
> + 
> ++
> +     a = - 1;
> +     b = nb_entries;
> + 
> +@@ -1675,6 +1707,11 @@
> +         timestamp = av_rescale(timestamp, st->time_base.den, AV_TIME_BASE * (int64_t)st->time_base.num);
> +     }
> + 
> ++    /* if we've built a seek table, use it. */
> ++    st = s->streams[stream_index];
> ++    if (st->seek_table.flags & AV_SEEKTABLE_FINISHED)
> ++        return av_seek_frame_table(s, stream_index, timestamp, flags);
> ++
> +     /* first, we try the format specific seek */
> +     if (s->iformat->read_seek)
> +         ret = s->iformat->read_seek(s, stream_index, timestamp, flags);
> +@@ -1712,9 +1749,367 @@
> +     // try some generic seek like av_seek_frame_generic() but with new ts semantics
> + }
> + 
> ++
> + /*******************************************************/
> ++int av_table_search_timestamp(AVStream *st, int64_t wanted_timestamp,
> ++                              int flags)
> ++{
> ++    AVIndexEntry *entries= st->seek_table.index_entries;
> ++    int nb_entries= st->seek_table.nb_index_entries;
> ++    int a, b, m;
> ++    int64_t timestamp;
> + 
> ++    a = - 1;
> ++    b = nb_entries;
> ++
> ++    //optimize appending index entries at the end
> ++    if(b && entries[b-1].timestamp < wanted_timestamp)
> ++        a= b-1;
> ++
> ++    while (b - a > 1) {
> ++	//TODO: since we have a lot of contiguous entries in the table, we can use something more
> ++	//like dictionary search, which will speed things up quite a bit.
> ++        m = (a + b) >> 1;
> ++        timestamp = entries[m].timestamp;
> ++        if(timestamp >= wanted_timestamp)
> ++            b = m;
> ++        if(timestamp <= wanted_timestamp)
> ++            a = m;
> ++    }
> ++    m= (flags & AVSEEK_FLAG_BACKWARD) ? a : b;
> ++
> ++    if(!(flags & AVSEEK_FLAG_ANY)){
> ++        while(m>=0 && m<nb_entries && !(entries[m].flags & AVINDEX_KEYFRAME)){
> ++            m += (flags & AVSEEK_FLAG_BACKWARD) ? -1 : 1;
> ++        }
> ++    }
> ++
> ++    if(m == nb_entries)
> ++        return -1;
> ++    return  m;
> ++}
> ++
[...]
> ++static int av_fill_table_internal(AVFormatContext *s, AVPacket *pkt, ByteIOContext *pb)

lots of code duplication

[...]

-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

I know you won't believe me, but the highest form of Human Excellence is
to question oneself and others. -- Socrates
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 189 bytes
Desc: Digital signature
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-soc/attachments/20100616/1eed1ba1/attachment.pgp>