Video Compression

VideoNerd

Enhancement of Error Resilience by Non-reference P Frames

  Content Idea How much non-Reference P-framing impacts on the video quality? Nvidia Rate Control has a flaw   Idea For low-latency applications like Cloud Gaming, in case of packet losses a retransmission is not feasible. Consequently visual distortions are observed for a while, due to temporal prediction, if the previous frame is corrupted then […]

Git Commands in Single Figure

How Git commands work from ByteByteGo.com   Slava23+ years’ programming and theoretical experience in the computer science fields such as video compression, media streaming and artificial intelligence (co-author of several papers and patents). the author is looking for new job, my resume Donate videonerd.website

Banach-Tarski Theorem and Philosopher’s Stone

Banach-Tarski Theorem  and Philosopher’s stone  or  How Become Billionaire Banach-Tarski Theorem says: “It is possible to decompose a solid sphere into a finite number of pieces, which can then be reassembled to create two spheres identical to the original” In other words, if you have a golden brick, then you can decompose it in a […]

Number Cores of AWS machine g4dn.4xlarge for Real-Time Transcoding with x264

The purpose of this note is to estimate the number of cores AWS machine (g4dn.4xlarge) required to transcode in real-time an encoded 1920x1080p@60fps video with the SW codec x264 to lower bitrate and/or to lower framerate and/or to lower resolution.  Actually our transcoding is both trans-rating and trans-scaling.   Testing methodology AWS machine:  g4dn.4xlarge Each […]

Python Script To Get Info on Cookies

A cookie is a small piece of data that the server sends in a Set-Cookie header as a part of the response in HTTP (or HTTPS). The client stores cookies locally and includes them in any future requests that are sent to the server. Thus, servers use cookies to track a client, its history etc. […]

Python Script To Download RFC Document

All internet protocols are specified in a special document, called RFC, moreover all RFCs are located at https://www.ietf.org/rfc/, for example UDP is specified by RFC 768. I wrote a script to download RFC document according to its number,  download_rfc.py   Usage: download_rfc.py [options]   Options:   -n                  RFC number   -o                 output rfc-file in txt-format […]

Python Scripts for Computer Vision

Content How To Decode and Show Frames Activation Web-Camera in Real-Time How to detect Faces with cvlib     How To Decode and Show Frames The python module sk-video  (to install this module pls. type ‘pip install sk-video’) contains a special iterator FFmpegReader to traverse (to decode) over all frames from any container (mp4,mkv,avi …).  The […]

Differential Pulse Code Modulation (DPCM) Method to Exploit Spatial Redundancy

The Spatial Redundancy in video data means a strong correlation of neighboring pixels, which is observed within frames. Therefore, a predictive coding is beneficial if the correlation is strong enough among the spatially adjacent pixels. The basis of the spatial predictive coding is to predict a pixel value from previous pixels which were already coded […]

AVS2 Open Source Encoder xavs2

Content AVS2  – Build and Run Run AVS2 by means of ffmpeg       AVS2  – Build and Run AVS2 is Chinese video encoding standard (the successor of AVS), for more info go to here   How to get and Build  AVS2 open-source encoder xavs2? git clone https://github.com/pkuvcl/xavs2.git  as recommended in the github of […]

Stability of System Linear Equations and Condition Number

Let’s consider the system of linear equations in the matrix form:   A x = b If we make tiny changes in the vector ‘b’ and the solution ‘x’ will change a little then the matrix ‘A’ is called stable. Otherwise, if any tiny change of the vector ‘b’ provides strongly different solution ‘x’, then […]