I can play the .avi file fine in VLC, but when I capture a clip of it, the clip file has no audio. I don't understand, because it must have the necessary codec to play the audio on the full video, right? But it can't output?
Version 2.2.1 Terry Pratchett (Weatherwax) (Intel 64bit)
thanks
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I want to add a 5.1 .flac audio track to a .ts file that already has three audio tracks. I tried with tsMuxer and ffmpeg with unsuccessful results. In tsMuxeR the .flac track is not recognized and in ffmpeg everything seems to work fine until the very last moment when I check the file and the .flac audio track is not included in the "output.ts". The .flac track is about 3GB and its lenght is around two and a half hours.
Thank you so much.
I don't think you'll find any existing software that maps FLAC into a MPEG-2 Transport Stream.
This gives you an idea what sort of issues you run into: https://xiph.org/flac/ogg_mapping.html
Let's say you came up with a reasonable way of mapping FLAC into a MPEG-2 Transport Stream - there won't be anything reading it.
Unless there is a specified way of mapping FLAC into a MPEG-2 Tranport Stream - you are on your own.
But PCM is supported in a MPEG-2 Transport Stream (for example Blu-Ray).
I'd use ffmpeg to transcode your audio from FLAC to PCM and then mux it into your transport stream.
Your audio transcode (FLAC to PCM) is lossless.
i have 2 video streams,
DVD is a big (4.6 GB) iso file white a dutch audio track (it's my own dvd)
Mp4 is a small (800MB) mp4 file white a eng audio track.
I search for a tool that van pick the audio track from the DVD and place it in the mp4, how can i do this?
jens.
Handbrake did the job, everything works find now.
I got some audio pieces in flv format. Each of them is about 10 seconds long.
My question is how to detect whether the audio pieces has "sound", in other words, sometimes the audio pieces has no sound even the size of it is not 0 byte, so how to find those broken/silent audio files by some linux tool/command?
Maybe ffplay can do this? any available advice?
If you want to quickly check if the stream is video only, audio only or if it contains both audio and video, try hexdump -C filename | head. The fifth byte contains information about the contents of the file.
0x01 - video only
0x04 - audio only
0x05 - audio + video
You can also try to play the file using VLC media player. There is a menu option that enables informational messages from the media being played back.
I'm working on MP4 muxing software that takes input from a hardware H.264 encoder and AAC-LC encoder. The file I produce plays OK in VLC, but audio is silent in Quicktime or when loading into Sony Vegas. If I "convert" the file through VLC to another .mp4, or use Handbrake to convert it, then audio works in Quicktime or Vegas from the resulting file.
Here is an example file I produced (8MB, 5 sec) which demonstrates the problem.
I'm picking through mp4 headers at the moment playing spot-the-difference but not coming up with much.
Any clues on debugging this, useful analysis utilities etc, would be welcome.
For the past few days, I have been trying to get my lossless .mov video(that has an audio track) to a .webm format.
Some info on the video & audio is that the fps is 30. Also the audio track has about 3-5 seconds of silence/blank audio before you start hearing some music.
My problem is that is seems during the transcoding to webm, it strips away this blank audio because when I go to play the video, the audio starts right away.I've also notice that it jumps right away to ~4 seconds in the video. When i play it on the browser, it jumps to that moment in the timeline. If I try to scrub to the beginning, the video ends.
I've have figured somethings out.
This is just a webm problem. This does not happen with ogv or mp4
It only happens if they is blank audio in the beginning of the audio track.
I am using ffmpeg with the libvpx and libvorbis librarys and I am doing just the basic command line setup
ffmpeg -i "infile" "outfile.webm"