Failed to set value '0' for option qscale

[JakeTheSnake3p0]

I have a test file downloaded from

http://www.youtube.com/watch?v=C0DPdy98e4c

and saved as a webm and flv using Flash Video Downloader. The files are named test.flv and test.webm. When testing my model, I get transcoding errors from ffmpeg.

1. It says ffmpeg is being deprecated in favour of avconv.

2. Seems stream 0 codec frame rate differs from container frame rate: 1000.00 (1000/1) -> 25.00 (25/1)

3. qscale must be > 0.0 and <= 255

4. Failed to set value '0' for option 'qscale'

ffmpeg reports version 0.8.10-6.0.8.10-0ubuntu0.13.10.1

These issues occur for both the flv and webm files. I also did another test with an .avi file downloaded from the web (not using FLV downloader) and I also get these issues.

[rheaton]

Can you get it to transcode via the command-line or the streamio-ffmpeg gem?

[JakeTheSnake3p0]

Can you provide a sample script that your app generates based on a simple conversion to mp4 so I can test it, or does your app log the command that is run using Rails.logger? If not, that would definitely be a helpful debugging tool.

[JakeTheSnake3p0]

I just tried a direct command to convert via ffmpeg. It's complaining because qscale cannot be set at 0. It must be greater than 0. I also had to use -strict experimental because ffmpeg complained about aac or something.

i.e., this didn't work: ffmpeg -i spec/models/files/test.webm -vcodec mpeg4 -qscale 0 -strict experimental spec/models/files/test-output.mp4

whereas this did: ffmpeg -i spec/models/files/test.webm -vcodec mpeg4 -qscale 0.1 -strict experimental spec/models/files/test-output.mp4

So this app is setting qscale to 0 when it should be greater than 0 and less than or equal to 255 (according to ffmpeg).

[JakeTheSnake3p0]

I modified my uploader to the following as a 'workaround' to the adverse defaults as well as other issues not related to the gem:

process encode_video: [:mp4, resolution: :same, video_bitrate: :same, custom: '-qscale 1 -acodec aac -strict experimental']

FWIW I also had to install other codecs via sudo apt-get install ubuntu-restricted-extras. Even with that, I got errors stating a problem with libfaac (which is why I used -strict experimental). It seems to be working now.