[FFmpeg-devel] [PATCH 03/18 v2] avformat/id3v2: allow ID3 parsing without AVFormatContext

[Anssi Hannula]

31.12.2013 04:37, Michael Niedermayer kirjoitti:
> On Tue, Dec 31, 2013 at 03:53:35AM +0200, Anssi Hannula wrote:
>> Add ff_id3v2_read_dict() for parsing without AVFormatContext, but
>> instead with AVIOContext and AVDictionary.
>>
>> AVFormatContext is still used for logging, if available.
>>
>> Chapter parsing is the only non-logging functionality that actually
>> needs AVFormatContext, and AFAICS it should be modified to write the
>> data to ID3v2ExtraMeta first, from where it can be implanted to
>> AVFormatContext by a separate function (like it is done with
>> read_apic() and ff_id3v2_parse_apic()). That is outside the scope of
>> this patch, though.
>>
>> Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
>> ---
>>
>> Updated to keep possibly NULL AVFormatContext around for av_logs.
>>
>>
>>  libavformat/id3v2.c | 101 ++++++++++++++++++++++++++++++----------------------
>>  libavformat/id3v2.h |  16 ++++++++-
>>  2 files changed, 74 insertions(+), 43 deletions(-)
>>
>> diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
>> index 54c85d1..de9e0c4 100644
>> --- a/libavformat/id3v2.c
>> +++ b/libavformat/id3v2.c
>> @@ -532,6 +532,9 @@ static void read_chapter(AVFormatContext *s, AVIOContext *pb, int len, char *tta
>>      int taglen;
>>      char tag[5];
>>  
>> +    if (!s)
>> +        return;
> 
> maybe add a debug av_log() here saying that it was skiped

Will add. I'll also add a short comment here saying what I have in
commit message regarding it not using ID3v2ExtraMeta instead.

> 
> [...]
>> @@ -861,14 +865,15 @@ error:
>>      if (reason)
>>          av_log(s, AV_LOG_INFO, "ID3v2.%d tag skipped, cannot handle %s\n",
>>                 version, reason);
>> -    avio_seek(s->pb, end, SEEK_SET);
>> +    avio_seek(pb, end, SEEK_SET);
>>      av_free(buffer);
>>      av_free(uncompressed_buffer);
>>      return;
>>  }
>>  
>> -void ff_id3v2_read(AVFormatContext *s, const char *magic,
>> -                   ID3v2ExtraMeta **extra_meta)
>> +static void ff_id3v2_read_internal(AVIOContext *pb, AVDictionary **metadata,
>> +                                   AVFormatContext *s, const char *magic,
>> +                                   ID3v2ExtraMeta **extra_meta)
>>  {
> 
> static functions dont need ff_ prefixes

Right, forgot to remove that.

> patch LGTM except these

OK, will apply after these.

-- 
Anssi Hannula