Adaptive differential pulse-code modulation (ADPCM) is a variant of differential pulse-code modulation (DPCM) that varies the size of the quantization step, to allow further reduction of the required bandwidth for a given signal-to-noise ratio.
Questions tagged [adpcm]
37 questions
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Algorithm for converting PCM to IMA ADPCM?
I have an algorithm for decompressing IMA ADPCM from http://wiki.multimedia.cx/index.php?title=IMA_ADPCM, but no way to re-compress it back to IMA ADPCM. Is there a simple pseudo code description, or do I have to reverse engineer it from the…
skagzilla
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acmStreamConvert - destination buffer is always empty
I have an encoded adpcm file (sample rate is 9600 and bit depth is 4) and I want to play it with NAudio.
I read the file with RawSourceWaveStream and then do:
var reader = new RawSourceWaveStream(new MemoryStream(File.ReadAllBytes(path)), new…
Maya
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Play Dialogic ADPCM audio file with NAUDIO
I am trying to play a Dialogic ADPCM file (no RIFF header) with the NAUDIO library. I have tried a couple of different things but have been unsuccessful so far. I tried a simple wav conversion:
FileStream fs = new…
user3272123
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Where to get simple opensource adpcm C\C++ encoder lib?
Where to get simple opensource pcm to adpcm C\C++ encoder lib?
Rella
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What is the algorithm of converting pcm to adpcm?
What is the algorithm of converting pcm to adpcm?
Rella
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1 answer
Windows Phone xaudio2
Hej
I am using a library for playing audio in Windows Phone found here.
Which works fine.
I am then trying to add a new .wav file to this system. And I get a memory error. Searching around on the internet gives me that I have to encode the audio…
JTIM
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Play ADPCM streams with Pygame
I've got some raw ADPCM compressed audio streams and I want to play them with pygame, but as far as I know this isn't possible with pygame. How can I decompress them with python to normal PCM streams (or something else pygame can play) and then play…
user2746752
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Cant play adpcm audio file with naudio
I try to play an adpcm alaw (i think its g.723 adpcm 40) file with NAudio without success.
the file is stereo sample rate is 8000 and the bit depth is 16.
when i try to create the adpcm alaw format with 2 channels i got an acm not possible error.
(…
Dudi Keleti
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Does ADPCM has some sample rate?
ADPCM is adaptive, so it has varible sample rate. But does it have some average rate or something? Does it have frames of fixed time duration?
Dims
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ffmpeg equivalent for sox -t ima
I am trying to use ffmpeg to combine 1 audio file (ADPCM) and 1 video file (h264) into single mp4. Video by file conversion works fine but ffmpeg chokes on guessing audio input. I can't figure out how to tell ffmpeg which params to use to decode raw…
LucasM
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How to make encoding/decoding huge amount of PCM samples to IMA ADPCM samples faster?
I want to encode wav files to IMA ADPCM as fast as possible.
But when I try to encode my file (1:39 length, 44100 sample rate, 16 bits, stereo), it takes ~8 seconds to encode it...
Is there a way to make it faster? Because 8 seconds looks pretty…
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How to save adpcm data to file like wav, mp3 in phone system?
There are telephone communication systems as follows.
Among these, I am going to develop a repeater.
The repeater performs tcp/ip communication.
Receive adpcm data in bytes from user1 and user2, respectively.
I want to save the data received from…
playground
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Play IMA ADPCM Audio with NAudio
I have a file with no header with IMA ADPCM raw data stored, I would like to play it using NAudio.
In Audacity, using this config plays without problems:
Encoding: VOX ADPCM
Byte order: No Endianness
Channels: 1 Channel (Mono)
Start offset: 0…
jms2505
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IMA ADCPM to Wav
I have a byte array with IMA ADCPM data stored, readed from a special file format. I would like to know how I could write it in a .WAV file. The rate/frequency is 32000 Hz and only has 1 channel (mono).
I'm not experimented in writing audio files…
jms2505
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How to decode filename.g726 coded information?
I have tried all ways to play the g726 codec file but not able to found decoder or how to play the g726 file.
I have tried with ffmpeg,mplayer,aplay.
deep shah
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