[FFmpeg-devel] [PATCH]lavf/latmenc: Error out for invalid codecs

[James Almer]

On 11/1/2017 11:23 AM, Carl Eugen Hoyos wrote:
> 2017-11-01 14:39 GMT+01:00 Paul B Mahol <onemda at gmail.com>:
>> On 11/1/17, Carl Eugen Hoyos <ceffmpeg at gmail.com> wrote:
>>> 2017-11-01 13:32 GMT+01:00 Paul B Mahol <onemda at gmail.com>:
>>>> On 11/1/17, Hendrik Leppkes <h.leppkes at gmail.com> wrote:
>>>>> On Wed, Nov 1, 2017 at 11:09 AM, Paul B Mahol <onemda at gmail.com> wrote:
>>>>>> On 11/1/17, Hendrik Leppkes <h.leppkes at gmail.com> wrote:
>>>>>>> On Wed, Nov 1, 2017 at 10:44 AM, Paul B Mahol <onemda at gmail.com> wrote:
>>>>>>>> On 10/31/17, Michael Niedermayer <michael at niedermayer.cc> wrote:
>>>>>>>>> On Mon, Oct 30, 2017 at 11:51:30PM +0100, Carl Eugen Hoyos wrote:
>>>>>>>>>> Hi!
>>>>>>>>>>
>>>>>>>>>> Attached patch makes sure the loas muxer does not try to write
>>>>>>>>>> anything but aac and latm.
>>>>>>>>>>
>>>>>>>>>> Please comment, Carl Eugen
>>>>>>>>>
>>>>>>>>>>  latmenc.c |    4 ++++
>>>>>>>>>>  1 file changed, 4 insertions(+)
>>>>>>>>>> 2b64f3d5ecb189e77b85dbab7a6cbfe9657701f2
>>>>>>>>>> 0001-lavf-latmenc-Error-out-for-invalid-codecs.patch
>>>>>>>>>> From 9f8f39b402f77b53613a395129f96feee5e873ba Mon Sep 17 00:00:00
>>>>>>>>>> 2001
>>>>>>>>>> From: Carl Eugen Hoyos <ceffmpeg at gmail.com>
>>>>>>>>>> Date: Mon, 30 Oct 2017 23:49:29 +0100
>>>>>>>>>> Subject: [PATCH] lavf/latmenc: Error out for invalid codecs.
>>>>>>>>>
>>>>>>>>> isnt AV_CODEC_ID_MP4ALS supported too ? (i see ALS related code in
>>>>>>>>> latmenc.c)
>>>>>>>>
>>>>>>>> How, when demuxer doesn't support it?
>>>>>>>
>>>>>>> Isn't ALS basically an extension of AAC? It would make sense that it
>>>>>>> can also go into LATM/LAOS.
>>>>>>
>>>>>> But do we actually supports it? There is no ALS encoder, and only way to
>>>>>> trigger
>>>>>> that is via -c copy.
>>>>>
>>>>> And thats a problem why?
>>>>
>>>> Untested path.
>>>
>>> But that seems unrelated to this patch, no?
>>
>> Its related because you are adding codec which is not going to work.
> 
> Sorry, I don't understand:
> Some developers claim that als-in-loas muxing will work, you doubt it.
> (I don't know, it's not easy to test and I don't find the spec atm.)
> Now you are saying that if I prevent anything but aac, latm and als
> from being muxed into loas, I am adding non-working code?
> 
> Please elaborate, Carl Eugen

I guess he's saying we'd be muxing files we wouldn't be able to demux,
which is a bad practice as we can't really test them.
Sort of like how we create animated Webp files we can't demux/decode.