[Ffmpeg-devel] [PATCH] Read AVI tags

[Michael Niedermayer]

Hi

On Tue, Aug 15, 2006 at 03:25:07PM -0400, David Conrad wrote:
> On Aug 15, 2006, at 4:00 AM, Benjamin Larsson wrote:
> 
> >Hi,
> >
> >David Conrad skrev:
> >>On Aug 15, 2006, at 1:39 AM, David Conrad wrote:
> >>
> >>>Hi,
> >>>The following patch adds some read support for metadata tags in  
> >>>AVI files. One note: the artist tag is put in the author field  
> >>>since there is no AVI tag for author, but this seems to be the  
> >>>same behavior as the mp3 parser's id3 tag reader.
> >>
> >>My apologies, please ignore that last patch. The correct one follows.
> >>
> >>-David
> >>
> >
> >can you implement writing also ? You can look here for a patch  
> >noone cleaned up enough to commit. http://thread.gmane.org/ 
> >gmane.comp.video.ffmpeg.devel/28596/focus=28596
> 
> Okay, I cleaned up that patch for writing, and I think I addressed  
> all of your and Micheal's concerns with the original. One thing,  
> though, is that the hash for the two test AVI files for ffserver  
> changed for me; the original patch doesn't indicate this.
> 
> -David

> Index: libavformat/avienc.c
> ===================================================================
> --- libavformat/avienc.c	(revision 5999)
> +++ libavformat/avienc.c	(working copy)
> @@ -89,6 +89,19 @@
>      return tag;
>  }
>  
> +static void avi_write_info_tag(ByteIOContext *pb, const char *tag, const char *contents)
> +{
> +    int len = strlen(contents);
> +    if (len > 0) {
> +        len++;
> +        put_tag(pb, tag);
> +        put_le32(pb, len);
> +        put_buffer(pb, contents, len);
> +        if (len & 1)
> +            put_byte(pb, 0);
> +    }
> +}

this could use put_strz()


[...]
> +    avi_write_info_tag(pb, "ISFT", "libavformat " AV_STRINGIFY(LIBAVFORMAT_VERSION));

this should be under CODEC_FLAG_BITEXACT check so regression tests dont break
if the version changes


> +    end_tag(pb, list2);
> +    list2 = start_tag(pb, "JUNK");
> +    for (i = 0; i < 1016; i += 4)
> +        put_le32(pb, 0);
> +    end_tag(pb, list2);

what is that good for?

[...]
-- 
Michael     GnuPG fingerprint: 9FF2128B147EF6730BADF133611EC787040B0FAB

In the past you could go to a library and read, borrow or copy any book
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