Cant create thumbnails from the trimmed videos

[slyvelikov]

Hi ya ! As you can see from the title Im trying to create a thumbnail using MediaMetadataRetriever and the method .setDataSource(), but Im getting this error in my logcat and no thumbnail visually - getFrameAtTime: videoFrame is a NULL pointer. If I dont trim the video everything works fine. Also Im stitching 2 videos and Im trimming either of them. But if the videos arent trimmed it can make a thumbnail.

[a914-gowtham]

Hi @slyvelikov , It is not reproducing. I tried to reproduce using below snippet. i take the first frame of the video.

public static Bitmap getFrameAt(Activity context, Uri videoUri) {
        try {
            MediaMetadataRetriever retriever = new MediaMetadataRetriever();
            retriever.setDataSource(context, videoUri);
            Bitmap res= retriever.getFrameAtTime(0);
            retriever.release();
            return res;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

and i pass Uri.parse(TrimVideo.getTrimmedVideoPath(result.getData())); to videoUri param.

try above snippet.

[slyvelikov]

Hi @a914-gowtham and thank you for your quick response ! Im able to load videos with your library and trimming them, the issue comes after I stitch the 2 videos. So I have an app that allows the customers to "stitch" 2 videos. This is done when you record a video with a pause then Im making small chunks of videos out of these pauses. And after I trim one of the these chunks and then stitch it together with the other video parts and I cant get the thumbnail. Ive tried your snippet but it didnt work. Could this be because of a codec issues between your library and my stitching function ?

[a914-gowtham]

@slyvelikov are you using ffmpeg for stitching. if yes, you could check if both trimmer library and stitch functuon uses same version of ffmpeg.

[slyvelikov]

Unfortunately, no, Im using file appending to "stick" them together.

[a914-gowtham]

could you share the sample code to append videos. @slyvelikov

[slyvelikov]

public void appendFile(File fileToAppend) throws VideoFileException {
    if (null == fileToAppend) throw new IllegalArgumentException();
    if (null == mBaseFile) {
        // If first pass, set fileToAppend as the base file
        mBaseFile = fileToAppend;
        return;
    }
    if (null != mOutputFile) {
        // If nth pass, set previous output file as the base file
        mBaseFile = mOutputFile.getFile();
    }

    if (!fileToAppend.getAbsolutePath().equals(mBaseFile.getAbsolutePath())) {
        mOutputFile = new VideoFile();

// Log.d(TAG, "Invoking service to append " + fileToAppend.getName() + " to " + mBaseFile.getName());
// Log.d(TAG, "Service to write composite file fileToAppend: " + fileToAppend.getAbsolutePath());
// Log.d(TAG, "Service to write composite file mBaseFile: " + mBaseFile.getAbsolutePath());
// Log.d(TAG, "Service to write composite file to: " + mOutputFile.getFile().getAbsolutePath());
//
// Log.d(TAG, "Service mCtx: " + String.valueOf(mCtx));
Intent i = new Intent(mCtx, VideoStitchingService.class);
i.putExtra(VideoStitchingService.INTENT_EXTRA_BASE_FILE, mBaseFile);
i.putExtra(VideoStitchingService.INTENT_EXTRA_FILE_TO_APPEND, fileToAppend);
i.putExtra(VideoStitchingService.INTENT_EXTRA_OUTPUT_FILE, mOutputFile.getFile());
mCtx.startService(i);
}
}

[slyvelikov]

I think the trimmed videos have been corrupted or MediaMetadataRetriever is perceiving them as corrupted.

[a914-gowtham]

I'm not sure if we can join two videos by file appending. but, merging two videos using ffmpeg will defenitely work.