[FFmpeg-devel] [PATCH] als in mp4

[Alex Converse]

On Mon, Mar 23, 2009 at 1:49 AM, Jai Menon <jmenon86 at gmail.com> wrote:
> On 3/23/09, Alex Converse <alex.converse at gmail.com> wrote:
>> On Mon, Mar 23, 2009 at 12:11 AM, Jai Menon <jmenon86 at gmail.com> wrote:
>> ?> On 3/21/09, Alex Converse <alex.converse at gmail.com> wrote:
>> ?>> On Sat, Mar 21, 2009 at 1:50 AM, Jai Menon <jmenon86 at gmail.com> wrote:
>> ?>> ?>
>> ?>> ?> Hi,
>> ?>> ?>
>> ?>> ?> Attached :
>> ?>> ?>
>> ?>> ?> 1) demux als streams from mp4, als codec id and minor lavc version bump
>> ?>> ?> 2) mux als in to mp4, add isomedia type
>> ?>> ?>
>> ?>> ?> --
>> ?>> ?> Regards,
>> ?>> ?>
>> ?>> ?> Jai
>> ?>> ?>
>> ?>>
>> ?>> > _______________________________________________
>> ?>> ?> ffmpeg-devel mailing list
>> ?>> ?> ffmpeg-devel at mplayerhq.hu
>> ?>> ?> https://lists.mplayerhq.hu/mailman/listinfo/ffmpeg-devel
>> ?>>
>> ?>>
>> ?>> > Index: libavformat/mov.c
>> ?>> ?> ===================================================================
>> ?>> ?> --- libavformat/mov.c ? ?(revision 18065)
>> ?>> ?> +++ libavformat/mov.c ? ?(working copy)
>> ?>> ?> @@ -426,6 +426,11 @@
>> ?>> ?> ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? st->codec->extradata_size);
>> ?>> ?> ? ? ? ? ? ? ? ? ?if (cfg.chan_config > 7)
>> ?>> ?> ? ? ? ? ? ? ? ? ? ? ?return -1;
>> ?>> ?> + ? ? ? ? ? ? ? ?if(cfg.object_type == 36) {
>> ?>>
>> ?>> > + ? ? ? ? ? ? ? ? ? ?st->codec->codec_id = CODEC_ID_MP4ALS;
>> ?>> ?> + ? ? ? ? ? ? ? ? ? ?st->codec->codec_type = CODEC_TYPE_AUDIO;
>> ?>>
>> ?>> > + ? ? ? ? ? ? ? ? ? ?return 0;
>> ?>> ?> + ? ? ? ? ? ? ? ?}
>> ?>> ?> ? ? ? ? ? ? ? ? ?st->codec->channels = ff_mpeg4audio_channels[cfg.chan_config];
>> ?>> ?> ? ? ? ? ? ? ? ? if (cfg.object_type == 29 && cfg.sampling_index < 3) // old mp3on4
>> ?>> ?> ? ? ? ? ? ? ? ? ? ? st->codec->sample_rate = ff_mpa_freq_tab[cfg.sampling_index];
>> ?>>
>> ?>>
>> ?>> I hope this isn't too bikeshedy but can this be made part of the
>> ?>> ?codec_get_id section below.
>> ?>
>> ?> It can and it should be. But as i said, the reference codec does not
>> ?> write the channel config correctly. So some if(codec_id != MP4ALS)
>> ?> will still be required. So it will still look like a hack ;)
>> ?>
>>
>>
>> Do you mean it's incorrect or do you mean it's set to zero? AAC still
>> ?works fine when it's set to zero.
>
> It's set to zero, which i think implies that the value should be read
> from als specifc config (what i understood from the spec). But as of
> now, the code doesn't check if any of the values read from the audio
> config object are zero, instead, it just overwrites the values which
> were set initially in the codec context (and which happened to be
> correct).
>

When were they initially set to the correct values?

--Alex