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Questions tagged [aac]

Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bit rates.

Advanced Audio Coding (AAC) is a standardized, lossy compression and encoding scheme for digital audio. Designed to be the successor of the MP3 format, AAC generally achieves better sound quality than MP3 at similar bit rates.

AAC has been standardized by ISO and IEC, as part of the MPEG-2 and MPEG-4 specifications.[3][4] Part of the AAC known as High-Efficiency Advanced Audio Coding (HE-AAC) which is part of MPEG-4 Audio is also adopted into digital radio standards like DAB+ and Digital Radio Mondiale, as well as mobile television standards DVB-H and ATSC-M/H.

AAC can be encapsulated in MP4, ADTS and ADIF formats. Use as well if the question is related to AAC encapsulated in ADTS and if the question is related to AAC encapsulated in MP4 container.

More information at AAC in wikipedia

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How to play m3u8 on Android?

As i understood, Android 3.0 and above are able for play radio streaming m3u8 - http://developer.android.com/guide/appendix/media-formats.html I put this link - http://content.mobile-tv.sky.com/content/ssna/live/ssnraudio.m3u8 into MediaPlayer but…
Saasha
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FFMPEG failing in AWS Lambda

I am trying to create a transcoding function for short videos. The function is hosted on AWS Lambda. The problem is that AWS lambda seems to be missing something that FFMPEG requires, at least according to Amazon. I contacted Amazon earlier and this…
Zaid Amir
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How can I get AAC encoding with ExtAudioFile on iOS to work?

I need to convert a WAVE file into an AAC encoded M4A file on iOS. I'm aware that AAC encoding is not supported on older devices or in the simulator. I'm testing that before I run the code. But I still can't get it to work. I looked into Apple's…
Sebastian
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ffmpeg wrong audio file after conversion in AAC

I have a problem with encoding in acc with FFmpeg. I have au mp4 file with aac audio. I tried to copy the audio with ffmpeg. In the source mp4 file, the first audio noise appears at 0.30 seconds. After conversion using ffmpeg -i inputfile.mp4 -c:a…
cybadr
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ALSA buffer xrun induced by low quality source in ffmpeg capture

I am attempting to transfer some old Video 8 tapes to my computer, though an EasyCap USB stick and the motherboard's sound line-in, on Ubuntu. I believe the arguments are correctly laid out below to capture from two independent streams, and encode…
Peter Becich
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FFmpeg - resampling from AV_SAMPLE_FMT_FLTP to AV_SAMPLE_FMT_S16 got very bad sound quality (slow, out of tune, noise)

I was confused with resampling result in new ffmpeg. I decode an AAC audio into PCM, the ffmpeg show audio information as: Stream #0:0: Audio: aac, 44100 Hz, stereo, fltp, 122 kb/s In new ffmpeg, the output samples are fltp format, so I have to…
kaienfr
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Encoding PCM (CMSampleBufferRef) to AAC on iOS - How to set frequency and bitrate?

I want to encode PCM (CMSampleBufferRef(s) going live from AVCaptureAudioDataOutputSampleBufferDelegate) into AAC. When the first CMSampleBufferRef arrives, I set both (in/out) AudioStreamBasicDescription(s), "out" according to…
user500
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Transcode HLS Segments individually using FFMPEG

I am recording a continuous, live stream to a high-bitrate HLS stream. I then want to asynchronously transcode this to different formats/bitrates. I have this working, mostly, except audio artefacts are appearing between each segment (gaps and…
rayh
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How to reduce size of moov atom of H.264 movies to improve streaming start for smartphones?

We run a video service streaming movies to smartphones (iOS&Android). We are encoding in H.264+AAC and using the mp4 container. We have a problem that long movies (60 minutes+) take a very long time to start playing and have tracked this down to…
Andrey Lebedev
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What does ffmpeg error "Prediction is not allowed in AAC-LC" mean?

When decoding AAC files, ffmpeg returns the error "Prediction is not allowed in AAC-LC". Does that mean the file is corrupt? Or that ffmpeg cannot handle AAC-LC files? I tried with different AAC files and get the errors: Number of scalefactor…
user2212461
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Looking for open-source library for editing AAC metadata (M4A files)

I'm looking for an open-source library for editing AAC metadata in M4A files (as appearing in iTunes). Specifically, I need to be able to add an album art tag. It should be something similar to id3lib, which works with ID3 tags on MP3 files.
Tim Norman
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AAC ADTS raw data strange header

I got some ADTS AAC raw data from somewhere(actually it is extracted from a demuxed file) and in theory it should be corrected encoded. it looks like this: Frame1: 21 19 94 ED A1 09 45 58 09 40 02 CA AA 85 D4 E5 C5 58 A9 73 00 0C 75 1C 5D A7 4E 52…
user991800
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Combine 2 AAC files using Java

I am trying to combine 2 AAC files into one, I found out that in AAC files - the header element is present till the FF8 byte, and then next 4 bytes contain the length of the data of the AAC. I tried to maintain 1 header array , add the size of the 2…
user1718827
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Encoding AAC with ffmpeg (c++)

I'm working on video encoding that will be used in a Unity plugin. I have made image encoding work, but now I'm at the audio. So trying only with the audio in to a mp4 file with AAC encoding. And I'm stuck. The resulting file does not contain…
Mockarutan
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Convert PCM to AAC or MP4 file without MediaMuxer

I need to convert a PCM file to AAC or MP4 file. Until now, I did it with MediaCodec and MediaMuxer, But MediaMuxer is supported from Android 4.3. Is there a method to do the conversion without the use of MediaMuxer? My code is this: MediaMuxer mux…
Luca Romagnoli
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