[FFmpeg-user] OpenCL? What Effect Does It Have

[Tom Evans]

On Wed, Aug 7, 2013 at 1:27 AM, James Board <jpboard2 at yahoo.com> wrote:
>>OpenCL can be used to accelerate the unsharp and deshake filters, as
>
>>documented in the filters documentation.
>
> Okay.  I saw that.  But are you saying that only those components of
> ffmpeg that are OpenCL accelerated?

Yes. Carl said it earlier too.

>>Generally the consensus (at least on here, as far as I can tell) is
>>that GPU assisted encoding is slow and gives crap results. YMMV.
>
> If optimized well, GPU assisted encoding would be extremely fast.
> I bet the people that coded the OpenCL encoders didn't have much
> GPU optimization experience.

I'm not talking about GPU encoding in ffmpeg, but GPU encoding in
general. It's not an uncommon opinion:

"""
The primary comparison here is between Xilisoft’s Ultimate Video
Converter, Arcsoft Media Converter, and Cyberlink’s MediaEspresso.
Other potential options, including Avivo, Badaboom, and MediaCoder are
discussed at the end of the article.
…
The TL;DR version of this article is as follows: If you want a video
encoder that’ll run on virtually any system, has well-thought,
easy-to-use presets, and neatly balances quality and file size, go
download Handbrake. It’s fast, free, and efficient — it just doesn’t
use the GPU.
"""

http://www.extremetech.com/computing/128681-the-wretched-state-of-gpu-transcoding

Handbrake, of course, being based around libav.

Cheers

Tom