[FFmpeg-devel] [PATCH v2 8/8] avfilter: add vsrc_ddagrab

[Timo Rothenpieler]

On 09.07.2022 07:01, Gyan Doshi wrote:
> 
> 
> On 2022-07-09 04:24 am, Timo Rothenpieler wrote:
>> ---
>>   Changelog                          |   1 +
>>   configure                          |   7 +
>>   doc/filters.texi                   |  68 ++
>>   libavfilter/Makefile               |   1 +
>>   libavfilter/allfilters.c           |   1 +
>>   libavfilter/version.h              |   2 +-
>>   libavfilter/vsrc_ddagrab.c         | 980 +++++++++++++++++++++++++++++
>>   libavfilter/vsrc_ddagrab_shaders.h | 120 ++++
>>   8 files changed, 1179 insertions(+), 1 deletion(-)
>>   create mode 100644 libavfilter/vsrc_ddagrab.c
>>   create mode 100644 libavfilter/vsrc_ddagrab_shaders.h
>>
>> diff --git a/Changelog b/Changelog
>> index 1a7c84b7f8..9467e92dd1 100644
>> --- a/Changelog
>> +++ b/Changelog
>> @@ -24,6 +24,7 @@ version 5.1:
>>   - VDPAU AV1 hwaccel
>>   - PHM image format support
>>   - remap_opencl filter
>> +- ddagrab (Desktop Duplication) video source filter
> 
> The source filters are all generative filters. This should be called a 
> capture filter.
> Why is it a filter instead of in lavd?

lavd has no infrastructure for hardware acceleration whatsoever, and 
returns packets, not frames.
There'd be no way to access the likes of -init_hw_device from lavd.

And it also seems pointless an extra indirection to put something that 
produces frames into lavd.
With the included patch for lavfi.c you can use it via lavd if you 
really want to.
Though you give up any control over the created hwdevice context.