[FFmpeg-devel] [PATCH] probe max read size

[Baptiste Coudurier]

Baptiste Coudurier wrote:
> Hi,
> 
> After some tests, it seems more reasonable to stop probing after some
> max size to avoid consuming to much memory.
> 
> I propose to raise probesize default to MAX_READ_SIZE
> 
> /* absolute maximum size we read until we abort */
> #define MAX_READ_SIZE        5000000
> 
> And also to replace all MAX_READ_SIZE occurence with s->probesize to
> make it configurable.
> 
> 
> 
> ------------------------------------------------------------------------
> 
> Index: libavformat/utils.c
> ===================================================================
> --- libavformat/utils.c	(revision 19024)
> +++ libavformat/utils.c	(working copy)
> @@ -523,7 +523,7 @@
>  
>  int av_read_packet(AVFormatContext *s, AVPacket *pkt)
>  {
> -    int ret, i;
> +    int ret, i, read_size = 0;
>      AVStream *st;
>  
>      for(;;){
> @@ -541,13 +541,16 @@
>  
>          av_init_packet(pkt);
>          ret= s->iformat->read_packet(s, pkt);
> -        if (ret < 0) {
> -            if (!pktl || ret == AVERROR(EAGAIN))
> -                return ret;
> +        if (ret < 0 && (!pktl || ret == AVERROR(EAGAIN)))
> +            return ret;
> +        if (ret < 0 || read_size >= s->probesize) {
>              for (i = 0; i < s->nb_streams; i++)
>                  s->streams[i]->probe_packets = 0;
>              continue;
>          }
> +
> +        read_size += pkt->size;
> +
>          st= s->streams[pkt->stream_index];
>  
>          switch(st->codec->codec_type){
> 

Well there is a problem in the patch, packet just read must be buffered
before "continue", this whole codec probing stuff is really non easy.

I'll check it tomorrow, if noones beats me ;)

-- 
Baptiste COUDURIER                              GnuPG Key Id: 0x5C1ABAAA
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