[FFmpeg-devel] [PATCH] libavcodec/libvpx: Add VPx alpha decode support

[James Almer]

On 7/15/2016 12:31 AM, James Zern wrote:
> On Tue, Jul 12, 2016 at 1:47 PM, James Almer <jamrial at gmail.com> wrote:
>> What's the first libvpx version that supports vp8a and vp9a?
>> Configure currently checks for 0.9.1 as the oldest supported
>> version for vp8 decoding, 0.9.7 for vp8 encoding, and 1.3.0 for
>> both vp9 components. We then use a bunch of ifdeffery to make
>> sure things compile with every version supported, so depending
>> on the answer to the above question this patch (and the one
>> adding vp9a enconding) may need to do the same, or it could be
>> a good reason to clean up things a bit and bump the minimum
>> required version for every component to for example 1.3.0.
> 
> This has come up before. I'm OK with bumping the minimum and will send
> something for that, though I'd say 1.4.0 (4/2015) is a better base for
> vp9; 1.3.0 could produce invalid bitstreams. Any objections?

I'm ok with bumping vp9 encoder requirement to 1.4.0. That alone
will clean a lot of ifdeffery, i bet. But don't change the other
three components unless there's a similar reason for it as with
vp9 enc (broken encoding or decoding prior to a certain version).