[FFmpeg-devel] GSoC

Dylan Fernando dylanf123 at gmail.com
Tue Mar 6 14:37:26 EET 2018


I am Dylan Fernando. I am a Computer Science student from Australia. I am
new to FFmpeg and I wish to apply for GSoC this year.
I would like to do the Video filtering with OpenCL project and I have a few
questions. Would trying to implement an opencl version of vf_fade be a good
idea for the qualification task, or would I be better off using a different

Also, I’m having a bit of trouble with running unsharp_opencl. I tried
ffmpeg -hide_banner -nostats -v verbose -init_hw_device opencl=ocl:0.1
-filter_hw_device ocl -i space.mpg -filter_complex unsharp_opencl output.mp4

but I got the error:
[AVHWDeviceContext @ 0x7fdac050c700] 0.1: Apple / Intel(R) Iris(TM)
Graphics 6100
[mpeg @ 0x7fdac3132600] max_analyze_duration 5000000 reached at 5005000
microseconds st:0
Input #0, mpeg, from 'space.mpg':
  Duration: 00:00:21.99, start: 0.387500, bitrate: 6108 kb/s
    Stream #0:0[0x1e0]: Video: mpeg2video (Main), 1 reference frame,
yuv420p(tv, bt470bg, bottom first, left), 720x480 [SAR 8:9 DAR 4:3], 6000
kb/s, 29.97 fps, 29.97 tbr, 90k tbn, 59.94 tbc
Stream mapping:
  Stream #0:0 (mpeg2video) -> unsharp_opencl
  unsharp_opencl -> Stream #0:0 (mpeg4)
Press [q] to stop, [?] for help
[graph 0 input from stream 0:0 @ 0x7fdac0418800] w:720 h:480 pixfmt:yuv420p
tb:1/90000 fr:30000/1001 sar:8/9 sws_param:flags=2
[auto_scaler_0 @ 0x7fdac05232c0] w:iw h:ih flags:'bilinear' interl:0
[Parsed_unsharp_opencl_0 @ 0x7fdac0715a80] auto-inserting filter
'auto_scaler_0' between the filter 'graph 0 input from stream 0:0' and the
filter 'Parsed_unsharp_opencl_0'
Impossible to convert between the formats supported by the filter 'graph 0
input from stream 0:0' and the filter 'auto_scaler_0'
Error reinitializing filters!
Failed to inject frame into filter network: Function not implemented
Error while processing the decoded data for stream #0:0
Conversion failed!

How do I correctly run unsharp_opencl? Should I be running it on a
different video file?

Best Regards,

More information about the ffmpeg-devel mailing list