The compression tag has no wiki summary.
2
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2answers
62 views
Usage of Digital Cosine Transform in lossy compression of images
I was reading about Digital Cosine Transform (DCT Type-I) and it's use in JPEG.
I have the following doubt. My teacher offered an explanation which wasn't very convincing.
What property of Digital ...
1
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0answers
39 views
How does Golomb-Rice Coding work?
I've read the explanation in http://urchin.earth.li/~twic/Golomb-Rice_Coding.html and http://en.wikipedia.org/wiki/Golomb_coding , however, I still not get the intuition why it is efficient and when ...
2
votes
1answer
118 views
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 ...
3
votes
1answer
132 views
What are some typical lossless compression ratios?
A client was trying to send me 250 GB worth of files. After attempting various ways of sharing the data, he sent me a zipped folder only 4 GB in size. That sounds like too much compression to me--I ...
3
votes
2answers
84 views
change the frequency component of a spectrum in an audio file
I am working on an audio dynamic range compressor using Matlab.
After calculating the FFT of the audio file, I use several bandpass filters to amplify specific bands separately.
What I want to do then ...
4
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2answers
101 views
Exam Question - end-to-end delay from video capture to video playout
Hi I'm preparing for my exam tomorrow and I've come across a 17 Mark question which seems trivially easy, so I think I'm missing a key point giving the rest of this exam is fairly difficult. The ...
2
votes
1answer
273 views
Speech Compression - In LPC how does the linear predictive filter work on a general level?
Hi I'm taking a multimedia systems course and I'm preparing for my exam on tuesday. I'm trying to get my head around LPC compression on a general level, but I'm having trouble with what is going on ...
7
votes
1answer
272 views
Theory behind Linear Predictive Coding (LPC)
What is the theory behind LPC? Why are(were) certain implementations of LPC said to be more tolerant of transmission or encoding errors quantization than other compressed voice encoding schemes?
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3
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2answers
92 views
A non-lossy aka lossless codec without patent-restrictions for audio?
The term non-lossy codec means the coding thing having no compression lost, more here. I need such format to process the audio, without destroying the quality. ...
2
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2answers
96 views
Compressing plotted data with variable sample rate?
I'm currently plotting high sample rate data by down-sampling by a factor and averaging. Most of the time this is working ok, but I am aware that at very low zoom levels (zoomed right out) the ...
4
votes
1answer
218 views
peak limiting/audio compression formula needed
I'm looking for a formula to effectively compress an audio waveform to limit peaks. This isn't an "automatic volume control" application where one would control amplifier gain to maintain a volume ...
3
votes
1answer
186 views
Determining the resulting pixel value before creating a compressed JPEG image
Is it possible to determine the resulting pixel values and modify them before the compressed jpeg image is actually created?
For example, I'm at the stage where I already have the quantized DCT ...
6
votes
1answer
218 views
Non-orthogonal basis which offers better energy compaction in image compression
I am aware of image-independent basis, i.e. DCT, and image-dependent basis, i.e. Karhunen–Loève, which are used in compacting energies for image compression. These bases are orthorgonal.
Are there ...
