I want to implement a python project in which the input will be a .mp4 file and the output will be the transcript or subtitle of the video. The constraint is to use OpenVINO. How can I do that?
mp4 is a container. I believe the current OpenVINO speech demo/samples use wav files as that is what the model is trained for.
If you can convert your mp3 or audio from the mp4 container using a tool to convert it to the wav format, that may work.
speech rec demo
I'm trying to make an audio upload to S3 and I'm a little confused what I should declare my mime type as. My audio file is an m4a recorded on an iphone as kAudioFormatMPEG4AAC. Would this be considered audio/m4a or audio/mp4? I'm seeing conflicting answers online.
The m4 in m4a is short-hand for MPEG-4, just like mp4 is short-hand for MPEG-4.
In fact, m4a, m4v and mp4 files all have the same internal MPEG-4 atom structure. The difference between the files is their content (video files have video atoms as well as audio atoms.)
The codec of the audio can also be different despite using the same file extension, for example both alac and AAC formats use the MPEG-4 container format with the m4a file extension.
So to answer your question, it really doesn't make much difference. My personal preference would be audio/mp4 since that is effectively saying
Audio data in MPEG-4 container
Whereas, audio/m4a is like saying
Audio data in MPEG-4 container containing audio
Use audio/mp4. audio/m4a may work, but it's invalid.
MP4 MIME type registration:
2. Selection of MIME Types for MP4 Files
The MIME types to be assigned to MP4 files are selected according to
the contents. Basic guidelines for selecting MIME types are as
follows:
a) if the file contains neither visual nor audio presentations, but
only, for example, MPEG-J or MPEG-7, use application/mp4;
b) for all other files, including those that have MPEG-J, etc., in
addition to video or audio streams, video/mp4 should be used;
however:
c) for files with audio but no visual aspect, including those that
have MPEG-J, etc., in addition to audio streams, audio/mp4 may be
used.
In any case, these indicate files conforming to the "MP4"
specification, ISO/IEC 14496-1:2000, systems file format.
Further, the list of standard MIME types includes audio/mp4, not audio/m4a, and non-standard MIME types should include “x-”, like audio/x-m4a.
In 2021 for me audio/mp4 for an .m4a file worked on Firefox + Chrome (Linux), Opera (Android) but not on iPhone Safari. For some formats the OS plays a role due to codecs.
I used a source tag with type attribute set and I also set the same type in the Content-Type header of the streamed / downloaded file.
https://en.wikipedia.org/wiki/HTML5_audio#Supported_audio_coding_formats
https://developer.mozilla.org/en-US/docs/Web/Guide/Audio_and_video_delivery/Cross-browser_audio_basics
https://developer.mozilla.org/en-US/docs/Web/HTTP/Configuring_servers_for_Ogg_media
Also see: How to play .m4a with HTML5 audio in IE(9+) and Safari (Pad)?
I have .mp4 file and I want to convert it to .webm with the same quality by avconv tool,
and vice from .webm to . mp4 with the same quality
document fuzzy to me.
That's not possible. WebM cannot contain MPEG media (video or audio.) So you can't repack ("remux") the media from mp4 to webm. You would need to re-encode them ("transcode" them), with VP8 or VP9 as the video format and Vorbis as the audio format. Thus you can't have the same quality, since transcoding from one lossy format to another always loses some quality.
So your only option is to transcode.
I have a case where i need to get audio out from video file. Is this possible in iOS ??
I need only the output file as an audio any type. I have the video file in my documents directory which I record earlier in application.
1.Convert Video Reverse
2.Extract audio from a video file
3.Add Audio & Video Together
Download Code From Here
may be helpful to you.
Yes, it can be done. See Extract audio from video file for ideas.
Extracting is probably the more accurate term.
I have several audio files which all of them are in .mp3 format. But playing .mp3 won't maximize the efficiency of audio playing on iOS. From one of research, .wav or .caf is a go for short loop or sound effect audio file used in game. Thus I need to convert this .mp3 file into those two formats.
Currently I use the following command to convert .mp3 to .caf.
afconvert -f caff -d LEI16 kick_sfx.mp3
However, I see that .caf is a container format thus I have a bad feeling that it's still not so efficient. According to that, I think I need to convert those .mp3 files to .wav first in order to maximize efficiency in playing audio file.
Do I need to really convert those (.mp3) files to .wav first before convert them again to .caf? Or using that command alone will do the work for me ?
Any additional info is welcome.