Encoder

[shatt...@gmail.com]

Hey!

I tried FFmpegFrameRecorder but it only worked with .avi and without setting the codec. The output file is too big I want better compression. If I set a codec I get the errors "Could not open video codec" or "Could not encode video packet".

I got these jars on the classpath:

ffmpeg-3.1.2-1.2.jar

ffmpeg-3.1.2-1.2-windows-x86.jar

javacpp-1.2.3.jar

javacv-1.2.jar

Do I need any extra binaries to use the codecs in avcodec class? For example I want to use AV_CODEC_ID_H264 (28). 

Thanks for the help!

Adam

[Frank Karlstrøm]

I have a slightly older version, but have the same libraries as you. 

What kind of error do you get? For Some extra info you should make sure javacv and ffmpeg logs correctly.

For javacv:

System.setProperty("org.bytedeco.javacpp.logger", "slf4j"); //set your desired level

For ffmpeg:

org.bytedeco.javacpp.avutil.av_log_set_level(avutil.AV_LOG_DEBUG); //debug is quite nice, it does not log so much, so debug is used in production

This is my code, that works OK (javacv 1.1 with friends):

For more info on H264 in FFMpeg, the presets, and fine tuning (if you are hardcore h264 expert) see:
https://trac.ffmpeg.org/wiki/Encode/H.264

FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(fileName, width, height, 0);

//Definition for H264

recorder.setVideoOption("crf", "29"); // Constant Rate Factor (23 is the default)

recorder.setVideoOption("preset", "fast"); // fast is actually fast, and gives better compression than normal on my type of video

recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);

recorder.setFormat("mp4"); // just the file format

// TODO We should use the frame rate from the original recording.

recorder.setFrameRate(15d); // FPS (frames per second)

recorder.setGopSize(30); // I really do not remember what this is, and i do not think it is necessary

Yours, Frank

[Samuel Audet]

Could you also provide the error message that you get on the console? It
should help diagnose this problem. Thanks!

Samuel

[shatt...@gmail.com]

I tried what Frank said.

FFmpegFrameRecorder recorder = new FFmpegFrameRecorder(new File("D:/new.mp4"), grabber.getImageWidth(), grabber.getImageHeight());

recorder.setVideoOption("crf", "29"); 

recorder.setVideoOption("preset", "fast"); 

recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264);

recorder.setFormat("mp4"); 

recorder.setFrameRate(grabber.getFrameRate());

recorder.setFrameRate(15d);

recorder.start();

This is what I get:

org.bytedeco.javacv.FrameRecorder$Exception: avcodec_open2() error -542398533: Could not open video codec.

at org.bytedeco.javacv.FFmpegFrameRecorder.startUnsafe(FFmpegFrameRecorder.java:590)

at org.bytedeco.javacv.FFmpegFrameRecorder.start(FFmpegFrameRecorder.java:294)

at VideoPlayer.start(VideoPlayer.java:48)

at VideoEditorFrame$6.run(VideoEditorFrame.java:310)

at java.lang.Thread.run(Thread.java:745)

[Samuel Audet]

Yes, ok, but could you also copy/paste the error messages that you get on the console?

If for some reason you do not get anything on the console, try to execute FFmpegLogCallback.set() first. Thank you

Samuel

[shatt...@gmail.com]

Oh, I knew I was missing something. :)

The first problem is: height not divisible by 2 (768x503)

http://pastebin.com/5sgRit3c

Then I tried setting the record frame height +1 pixel and it worked for like a few frames.

http://pastebin.com/d053YUkj

[Samuel Audet]

It looks like you're trying to set negative timestamps: That won't work.