Questions tagged [pcm]
PCM (Pulse-code modulation) is a method used to represent digital samples of the analog signals.
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Decoding aac to PCM in ffmpeg introduces noise in the raw PCM audio
I have a .mp4 file generated with ffmpeg as follows.
ffmpeg -y -i video_extended.mp4 -itsoffset 00:00:04.00 -i output5-1.wav -map 0:0 -map 1:0 -c:v copy -c:a aac -ac 6 -ar 48000 -b:a 128k -async 1 ...
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How does G729 Codec compress down to 8kbps?
As per https://en.wikipedia.org/wiki/G.729:
It has a sample frequency of 8kHz, so every second it takes 8000 Samples:
Sampling frequency 8 kHz/16-bit (80 samples for 10 ms frames)
It has a fixed ...
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Convert raw AAC data to PCM data via ffmpeg
I have a system which is transmitting raw AAC data via TCP (no ADTS frame/header). Each "packet" is prefixed with enough information for me to determine the length of the raw data. I also ...
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How to convert flac inside mkv ffmpeg?
Guys! I was wanting to know if anyone can tell me how to losslessly convert FLAC audio to LPCM without any quality loss at all?
This is info from of the mkv. Stream #0:0: Video, Stream #0:1: Audio: ...
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ALSA snd_pcm_hw_params_any crashed when auto-run from startup script
I downloaded the ALSA sample source codes (https://gist.github.com/ghedo/963382) and test running under putty window, it works. However when put into the startup script (eg. rc.local) with or without &...
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ffmpeg says "pcm_f32be codec not supported in WAVE format" yet a file is created
I'm trying to create a sine wave in .wav using ffmpeg exactly like this S.E. question: How to generate a sine wave with ffmpeg?
For some sample formats it's working good but for big endian encoding, ...
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Extracting audio, don't understand PCM options
I've got the audio bitdepth, frequency and channels down. Pretty simple to understand, but cannot find enough information on the different PCM formats.
I do understand the numbers correlate to the ...
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ffmpeg - How to prevent innacurate duration when converting from pcm to wav?
I have the following command:
ffmpeg -f f32le -ar 44100 -channels 2 -i input.pcm -y -acodec pcm_s16le -f wav output.wav
input.pcm is the pcm data that comes from a 2 seconds wav file. However, when ...
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How to encode into WAV ADPCM?
How to encode WAV PCM into WAV with ADPCM encoding?
I tried FFmpeg. I can see from the old FFmpeg codec list, that it previously supported encoding into adpcm_adx, adpcm_ima_qt, adpcm_ima_wav, ...
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How to convert raw PCM data to a valid WAV file with ffmpeg?
I run this command: ffmpeg -f f32le -i pipe:0 -f wav pipe:1
ffmpeg version 4.1-tessus https://evermeet.cx/ffmpeg/ Copyright (c) 2000-2018 the FFmpeg developers
built with Apple LLVM version 10.0.0 (...
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Using a ALSA PCM as an input device for Chromium?
I have a Matrix Creator which I want to use as an input for a speech to text platform, running through Chromium (using webkitSpeechRecognition). My problem is that I do not have it available as a ...
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FFmpeg raw audio and H264 in RTSP
Trying to grab correctly video and audio data from an IP camera Hikvision.
Everything works like a charm when doing so for H264 + MP2 for example.
When trying to grab RAW audio in PCM s16le - smile ...
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How accurate and reliable is loudness analysis (ebur128) in ffmpeg for PCM?
I need to test a lot of files on possible audio normalization issues, files can be of various containers and audio encoding formats but mostly PCM audio. I tried Rhozet QC solution but found it ...
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Is WAV (PCM) format bit rate is really CBR?
You know, all modern audio codecs bit rate modes are VBR, even if you restrict the settings to for example: MP3 128 CBR, the encoded result is between 120 to 135 ( a bit different with different ...
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How to extract Blu-ray audio without any conversion?
As avconv (forked from ffmpeg) said, the format of Blu-ray audio stream is called pcm_bluray, but why most of the tutorials say using -acodec pcm_s**le flag (** depends on its sample rate)?
Are they ...
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