I would use FFprobe (it comes along with FFMPEG): ffprobe -i INPUT -show_streams -select_streams a -loglevel error In case there’s no audio it ouputs nothing. If there is an audio stream then you get something like: [STREAM] index=0 codec_name=mp3 codec_long_name=MP3 (MPEG audio layer 3) profile=unknown codec_type=audio codec_time_base=1/44100 etc etc… [/STREAM] That should be easy enough … Read more
The following command will mute two sections: between 5-10s and 15-20s: ffmpeg -i video.mp4 -af “volume=enable=”between(t,5,10)”:volume=0, volume=enable=”between(t,15,20)”:volume=0″ … Description: -af is the audio filter. It works by specifying multiple volume filters that are enabled/disabled at the specified time. volume=enable=”between(t,5,10)”:volume=0 means use a volume filter that gets enabled between 5 and 10 seconds and sets the … Read more
Noise filters in audio recording sources on Android vary greatly from device to device. It isn’t until Ice Cream Sandwich that any sort of definition was put into the device compatibility document defining a method for not having filtering. That method id to use the MediaRecorder.AudioSource.VOICE_RECOGNITION audio source. Before that it’s just choose a setting … Read more
http://www.freesound.org/ Also, archive.org may have some stuff.
As suggested by the tool, try reducing the volume slightly, e.g. by preceding with -v 0.99 (or 0.98 etc.). Such small changes in volume are imperceptible. Example: sox -v 0.99 <source_wav> -b 16 <dest_wav> channels 1 rate 16000 trim <startTime> =<endTime> If you still get clipping then the audio is likely severely clipped (i.e. disorted) … Read more
Here is a graphic that illustrates the threshold approach to note onset detection: This image shows a typical WAV file with three discrete notes played in succession. The red line represents a chosen signal threshold, and the blue lines represent note start positions returned by a simple algorithm that marks a start when the signal … Read more
codec not currently supported in container ffmpeg does not support PCM (pcm_alaw, pcm_s16le, etc) in the MP4 container. Encode the audio as AAC, or use a different output container format such as MOV or MKV. Encode the audio to AAC ffmpeg -i input.mov -c:v copy -c:a aac output.mp4 Or output to MOV or MKV ffmpeg … Read more
Use the silenceremove filter. This removes silence from the audio track only – it will leave the video unedited, i.e., things will go out of sync Its arguments are a little cryptic. An example ffmpeg -i input.mp3 -af silenceremove=1:0:-50dB output.mp3 This removes silence at the beginning (indicated by the first argument 1) with minimum length … Read more
A cleaner solution (than the one given by user6026720) that fixes Simulator logs without affecting Device logs is available at https://stackoverflow.com/a/39651073/1033581: Under Product > Scheme > Edit Scheme… > Run, set the OS_ACTIVITY_MODE environment variable to ${DEBUG_ACTIVITY_MODE} so it looks like this: Go to your project build settings, and click + to add a User-Defined … Read more
You could first use ffmpeg to detect intervals of silence, like this ffmpeg -i “input.mov” -af silencedetect=noise=-30dB:d=0.5 -f null – 2> vol.txt This will produce console output with readings that look like this: [silencedetect @ 00000000004b02c0] silence_start: -0.0306667 [silencedetect @ 00000000004b02c0] silence_end: 1.42767 | silence_duration: 1.45833 [silencedetect @ 00000000004b02c0] silence_start: 2.21583 [silencedetect @ 00000000004b02c0] silence_end: … Read more