[FFmpeg-devel] [PATCH 1/2] docs/filters: add documentation to all existing OpenCL filters

[Gyan Doshi]

Danil,

On 04-08-2018 12:43 AM, Gyan Doshi wrote:
> 
> 
> On 03-08-2018 08:46 PM, Danil Iashchenko wrote:
> 
>> +For most general-purpose filters, no conversion is required.
>> +
>> +In case a file contains an alpha channel supported by the format, 
>> then explicit conversion is a requirement.
> 
> This is unclear. So, if the input's pixel format has alpha, we should 
> convert? to what? In the example below, the conversion target also has 
> alpha. Does RGB24 need to be converted?
> 
>> + at item
>> +Insert a PNG logo in the top-left corner of the INPUT. Explicit 
>> format conversion is a must.
>> + at example
>> +-i INPUT -i LOGO -filter_complex "[0:v]hwupload[a], 
>> [1:v]format=yuva420p, hwupload[b], [a][b]overlay_opencl, hwdownload" 
>> OUTPUT
> 
> PNGs, afaik, are always full chroma. Shouldn't we convert to yuva444p?

These are the only outstanding issues in this patch. Clarify them and I 
can push tomorrow.

Regards,
Gyan