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Listening to internet radio with FFplay

Listening to Internet radio Internet radios have web HTML players. While they are easy to use, you can’t customize sound and they are not much reliable. I switched to mpv player but its even less reliable than web players - plagued with Buffer underrun problems. FFplay Because I use FFmpeg daily, I took at look at its player FFplay. FFplay is part of FF multimedia framework and have access to its filters and decoders. [Read More]

Deinterlacing video using FFmpeg

Sometimes we receive interlaced video file because PAL or NTSC videos are interlaced. While it’s the best let video be in interlaced format, some video hosting services mess up interlaced input - they will reencode it, but don’t deinterlace or tag output as interlaced. This leads to wave like digital artefacts. Check our input Filter idet - interlace detection Lets test with ffprobe and idet filter our input. $ ffprobe -hide_banner "Round 06. [Read More]

Converting picture to WebP

Format WebP is open-sourced and royalty free optimised image format that provides superior lossless and lossy compression for images on the web. WebP is based on VP8 video codec created by Google. It’s supported by major browsers and major multimedia manipulation programs including FFmpeg and ImageMagick. FFmpeg WebP conversion Higher quality means larger file. It’s similar to JPEG quality. Range 0 - 100, default 75. compression_level can be up to 6. [Read More]

Converting picture to AVIF

Format AVIF is open-sourced and royalty free optimised image format. AVIF offers significant file size reduction compared with JPEG, PNG and WebP. AVIF is 30% smaller than WebP and 50% smaller than JPEG. AVIF is based on AV1 video codec created by Alliance for Open Media. It’s supported by major browsers and major multimedia manipulation programs FFmpeg and ImageMagick. FFmpeg conversion After some testing, I found that SVT-AV1 library works the best. [Read More]

Installing Redmine 5.0 on Windows

Let’s install Redmine 5.0 - flexible project management on Windows. Official installation instructions are here. Study them carefully. Here are my notes based on trial and error while attempting to install Redmine 5.0.3 on Windows 10. Same steps can be used for upgrading installation. Download Redmine 5.0 installation zip. Install scoop In scoop add versions bucket Use scoop install -g ruby27 msys2 Run ridk install to finish ruby installation. On prompt press ENTER. [Read More]

Simple FFmpeg audio mastering

Before releasing video, audio part need to be mastered. We already write about audio level normalization. Today, we focus on most common cases in applying equalizer to audio. Filter adeclip Removes some artefacts created by clipping and prints clipping statistics. Always use. It will not lower volume under 0.0 dbFS, in fact true peaks will be slightly raised. Filter volume If volume is too hot, use filter volume to lower true peaks under 0 dbFS. [Read More]

Simple H264 encoding with FFmpeg

Most common use case for processing video before sharing it on Internet is to normalize audio volume level and reduce video content bitrate. We will use patented H264 codec, High profile 4.2 for FullHD (1920x1080) footage. This profile is supported by iPhone 6, iPad mini and later models see here. Because we are running ffmpeg on command line manually and want just quick conversion we will use single pass encoding. [Read More]

50 Intermediate Codecs compared

One of most often linked pages in video editing tutorials is Compare 50 Intermediate Codecs. This page compares bitrates of several industry standard intermediate codecs: DPX, Cineform, DNxHD, DNxHR, ProRes.

Intermediate codecs are used during editing video. Their advantage over highly compressed codecs like VP9 or H265 is very fast decompression at cost of much larger files.

Distributed randomness

Organization called League of Entropy is working on providing decentralized randomness beacon. Software implentation is called drand. League of entropy runs public pool where anybody can get high quality randomness. Entropy is collected from high quality randomness sources, such as lava lamps. Pool endpoints are listed here. Here you can see pool metadata. Randomness is 32 bytes long and its changing every 30 seconds. You can get not only current randomness but also all past numbers. [Read More]