Questions tagged [mp3]
MP3 is a patented digital audio encoding format using a form of lossy data compression.
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Is there a Mcu/ DSP IC which can help me convert wav to MP3 (44.1 Khz sampling) in real time and store it into an embedded SD card?
I have built a Bluetooth speaker using an ESP32. It can stream BLE audio and play MP3/WAV from an embedded SD card. I want to record 44.1Khz res audio from it but unfortunately the ESP32 is not ...
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lossy vs. lossless audio format in machine learning
We want to provide an ML model that recognises diseases from the voice. The feature extraction is based on a proprietary algorithm. Normally we have always used wav files. We keep asking ourselves if ...
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How to identify the middle of the first trough in a waveform?
(Asked on CrossValidated before I found this community)
I have audio files and timestamped fragment transcriptions that I have force-aligned with third party software.
Unfortunately the software ...
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How do I reliably find the start/end of an MP3 audio frame without decoding it?
(I don't see a way of conveying the situation better than by providing a screenshot. Please pardon me.)
According to MP3 specs, the below depicted MP3 audio frame starts at ...
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Why does MP3 use modified DCT?
I read on Wikipedia MP3 that the MP3 standard uses a modified discrete cosine transform.
Why does it use a modified transform and not the original DCT like the JPEG standard? Are there reasons ...
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Which Audio Codec/Bitrate Relationship delivers best Audio Quality: 128 kbit/s MP3 vs. 192 kbit/s AAC vs. 64 kbit/s OPUS?
Assumed we have those three audio streams available for listening to:
MP3 with a bitrate of 128 kbit/s
...
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How to tell if a high-res flac file has been upsampled from a CD-quality file?
Because I might encode my music in lossy format for other devices or edit them, I prefer to keep a high-res copy of my music. However, I know that it is possible to upsample a file using ffmpeg and it ...
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A mp3 file is reeoncoded in a video software (shotcut), which bitrate (Audio Bitrate vs Lame Bitrate) do I need to use?
I have downloaded a .mp3 file from the internet. "Right click" and "Properties" on Linux does not show up any bitrate (N/A) in the "Audio" tab.
Then, I executed following ...
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Why removing noise increases my audio file size?
I took some mp3 files of people talk with noise in the background and then removed the background noise using online voice seperator tools (such as https://vocalremover.org/). I was surprised to find ...
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Questions about MP3 bitrate conversions
I was trying to analyse the lossy compression of MP3 audio files through their Spectrograms and the results were something like this (where the upper is 80Kbps and lower is 128Kbps).
It is obvious ...
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Can PSNR > 48 used to validate the signals between two audio files?
I have written some audio decoding code. I decoded an mp3 file and save as wav file.
In order to validate the code is working correctly, I compare the signal between the mp3 file and the decoded ...
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Is it possible for Matlab to read and decode an mp3 file?
I have run the following Matlab code and I got a signal as shown in the Figure below.
...
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Does a .wav file created from a .mp3 file have better quality than the .mp3 file itself?
A .wav file created from a .mp3 file has the same frequency domain plot as the mp3 file itself https://stackoverflow.com/questions/58706674/difference-between-frequency-domain-in-mp3-and-wav.
However,...
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How to interpret these MP3 spectrums?
Recently, I found I had this song duplicated in my music library, but when listening to them I noticed one version was of noticeably higher quality than the other despite both claiming to have a ...
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Extract frequency data from MP3 file
I want to do frequency analysis of audio data, basically trying to figure out what the notes are in a song algorithmically. The standard approach is to decode the MP3 into PCM data and run it through ...
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Length of padding for multiple samples stored in a single MP3 file
I have 20 short audio samples of a piano playing a single note. Due to internal limitations of my application, I need to concatenate and combine these into a single lossy file (either MP3 or AAC). ...
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Audio processing. Is it possible to directly access the decoded audio data going into the analog input of a computer
When a computer transcodes an audio file from one file format to another, does the computer first decode it into the raw digital stream (exactly what is fed into the DAC for the audio output) , or ...
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Does the sound volume affects the MP3 file size?
Let's say I have an X music track in some lossless format (wav?).
If I convert it to MP3 format with its original volume and get the file "A.mp3".
Then I edit the lossless source and reduce the ...
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Norm MPEG-1 Layer III (Mp3) Filter banks distortion
So, I'm working with the filter banks used in Mp3, in Matlab. I am obtaining quite a huge distortion in the output and I don't really know whether I'm making something wrong.
I've reviewed the ...
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Converting Google's text-to-speech voice to, say, Justin Bieber's voice
We are trying to convert text to an artist's voice. For example, we want input text in Justin Bieber's voice. We are converting text to mp3 files in Python using gTTS (Google Text-to-Speech). We can ...
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Does one ever store audio in mp3s with one channel being inverted?
As far as I am aware this is something one does for analog processing, not in digital, and one only does it during the actual processing and not in storage (for example in an mp3).
Is my thinking ...
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MP3 Filterbank + MDCT: Why?
What is the rationale for the two-step process the MP3 format performs, first decomposing the input into 32 subbands of 6/18 samples each then performing MDCT on each subband individually?
Why not ...
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Change pitch of mp3 audio on a microcontroller
I have an MP3 decoder running on a ESP32, and I'd like to change the pitch of the streaming audio in real time.
I plan to build a little toy that streams Amazon Alexa and changes her voice so that it ...
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References on the MP3 encoding algorithm
Does anybody have a reference describing the MP3 algorithm in a step-by-step manner and clear to understand?
These references were a little bit confusing:
Audio compression using modified ...
ali ha
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MP3 equalization
I made an equalizer using eq10q filters. Now I want to use my equalizer for music equalization and make my own music player. So I have some doubts:
If I want to equalize MP3 files, do I have to ...
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Why is an audio compressed in FLAC(Free Lossless Audio Codec) changing its bit rate?
I just recognized that the bit rate of an audio file compressed in FLAC is changing during play. On the other hand, MP3 file has a fixed bit rate such as 128, 192, 320kbsp etc. But why FLAC is not? ...
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Formatting issue WAV - MP3?
I have two "sources" of audio:
record WAV audio files (44.1kHz, 16bit, stereo) with Linux arecord and convert them with LameMP3Encoder to MP3 files (44.1kHz, 320kbps, 32bit**, CBR)***
record MP3 ...
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Will lossy compression prevent me from performing audio analysis?
I'm starting a project where we will have to analyze bird recordings. We will try to measure the birds activity using the audio.
The recordings are really long (around 24 hours each) and recorded in ...
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Downsampling MP3 for FM broadcast
I have some MP3s that are encoded at 44.1kHz with a bitrate of 160kbps. I hook these up to my car using an FM transmitter and the sound quality isn't particularly great. Low and high notes sound ...
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Difference between jpg compression and mp3 compression
My understanding of jpg compression is that, if done repeatedly, any image will eventually be reduced to a single flat color, due to the way it deals with neighboring pixels. However, years ago I was ...
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how to extract telephone audio only from an mp3
I have mp3s of radio talk shows in which the host interviews people on the phone. The host uses a microphone, and the interviewee uses either a landline phone or a cell phone.
I want to save just the ...
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Audible mp3 artifacts?
What kind of compression artifacts would typically be most noticeable to a non-audiophile listener in a low-bit rate mp3 (MPEG-2 Layer III) compressed audio file?
What kind of audio signal might one ...
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How to extract vocal part from stereo audio signal?
I'm now processing MP3 file and encounter this problem. My MP3 is stereo encoded. What I want to do is extract vocal part for further processing(whatever mode of output signals, mono or stereo are ...
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MP3 Decoding Discrepancy
Is it possible for two different decoders to output two different sample results for the same MP3? I'm decoding an mp3 on Matlab and it produces two columns (presumably one for each channel). When I ...
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