压缩的mp4视频播放时间过长（exoplayer）

Question

Video(mp4) is recorded from android camera and sent to backend, here I am using ffmpeg wrapper to compress the video[44mb video to 5.76mb]. compression is working well, But when I send the video for play in android(exo player), is taking too long time to start.

below is my code to compress:

 FFmpegBuilder builder = new FFmpegBuilder()
                   .setInput("D:/dummyVideos/myvideo.mp4")     // Filename, or a FFmpegProbeResult
                   .overrideOutputFiles(true) // Override the output if it exists
                   .addOutput("D:/dummyVideos/myvideo_ffmpeg.mp4")   // Filename for the destination
                   .setFormat("mp4")       // Format is inferred from filename, or can be set
                   .disableSubtitle()       // No subtiles
                   .setAudioChannels(1)         // Mono audio
                   .setAudioCodec("aac")       // using the aac codec
                   .setAudioSampleRate(48_000) // at 48KHz
                   .setAudioBitRate(32768)     // at 32 kbit/s
                   .setVideoCodec("libx264")     // Video using x264
                   .setVideoFrameRate(24, 1)     // at 24 frames per second 
                   .setVideoResolution(1280, 720) // at 640x480 resolution
                   .setVideoBitRate(762800)
                   .setStrict(FFmpegBuilder.Strict.EXPERIMENTAL) // Allow FFmpeg to use experimental specs
                   .done();

Can anyone tell me why video is taking too long time to play in exo player? Is anything wrong in the compression?

Answer 1

Based on comments I am writing ans here, Because of "moov" atom video is taking long time to play, Here's the described blog: https://rigor.com/blog/2016/01/optimizing-mp4-video-for-fast-streaming

code is:

try{
        QtFastStart.fastStart(inputFile, outputFile); // Adds moov to your input
                   // Now your output file is ready to stream!
        }catch (QtFastStart.MalformedFileException m){
            logger.error("QT", m);
        }catch (QtFastStart.UnsupportedFileException q){
            logger.error("QT", q);
        }catch (IOException i){
            logger.error("QT", i);              
        }