Basic attempt at injecting and reading back user data unregistered (UDU) supplemental enhancement information (SEI) with ffmpeg / libav.
Some references:
Tom Vercauteren tvercaut
tvercaut
/ wavelength_to_rgb.py
Last active
March 21, 2024 17:28
Simple python function to get an approximate RGB value for a given wavelength
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| #!/usr/bin/env python3 | |
| import numpy as np | |
| import matplotlib.pyplot as plt | |
| def wavelength_to_rgb(wavelengths, gamma=0.8): | |
| '''This converts a given wavelength of light to an | |
| approximate RGB color value. The wavelength must be given | |
| in nanometers in the range from 380 nm through 750 nm | |
| (789 THz through 400 THz). |
tvercaut
/ !RANSAC-based plane fitting - A rough batched PyTorch implementation.md
Last active
February 21, 2025 14:46
torch-fit-plane.ipynb
A simple PyTorch implementation of plane fitting with RANSAC. Some ideas are taken from: https://github.com/leomariga/pyRANSAC-3D.
In each (batched-)RANSAC iteration, a batch of triplets is sampled and assessed in parallel.
A cross-product is used to get plane equations from triplets.
The refinement, post identification of inliers, is done with an eigen decomposition of P.T @ P where P is the matrix of points in homogeneous coordinates.
Classicially, an SVD decomposition of P is used but this can be slow and memory intensive with large number of points.
We thus opted for the eigen decomposition approach despite it being less numerically stable.
tvercaut
/ !Muxing with meta
Last active
April 5, 2022 12:24
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| Hack file to get a nicer Gist name |
tvercaut
/ synthetic10bit.py
Created
October 28, 2021 08:28
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| import numpy as np | |
| import matplotlib.pyplot as plt | |
| import imageio | |
| url = 'https://archive.org/download/10thframekixxc64800dpi48bit/10th%20Frame%20%28Kixx%29_C64_Cassette_800dpi_48bit.tif' | |
| im0 = imageio.imread(url) | |
| print('im0:',np.min(im0),np.max(im0),im0.shape,im0.dtype) | |
| im0gray = 0.299*np.float32(im0[:,:,0]) + 0.587*np.float32(im0[:,:,1]) + 0.114*np.float32(im0[:,:,2]) | |
| im0gray = im0gray / np.max(im0gray) | |
| im1 = np.uint16(np.round( im0gray*((1<<10)-1) )) |
tvercaut
/ !spectra.md
Last active
July 5, 2022 15:33
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| #EXTM3U | |
| #EXTINF:0,Radio France - FIP (AAC+Metadata) | |
| http://radio-metadata.fr:8000/fip.m3u | |
| #EXTINF:0,Radio France - FIP Reggae (AAC+Metadata) | |
| http://radio-metadata.fr:8000/fipreggae.m3u | |
| #EXTINF:0,Radio France - FIP World (AAC+Metadata) | |
| http://radio-metadata.fr:8000/fipmonde.m3u | |
| #EXTINF:0,Radio France - FIP Nouveautés (AAC+Metadata) | |
| http://radio-metadata.fr:8000/fipnouveaute.m3u | |
| #EXTINF:0,Radio France - FIP Electro (AAC+Metadata) |
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| Hack file to get a nicer Gist name |
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| #!/bin/sh | |
| # Sanity checks | |
| if ! [ -x "$(command -v gs)" ]; then | |
| echo "gs is not installed -> exit" | |
| exit 1 | |
| fi | |
| # Define some handy options to use with ghostscript | |
| export PDF2PDFFLAGS="-dCompatibilityLevel=1.5 -dPDFSETTINGS=/ebook -dPrinted=false -dColorConversionStrategy=/UseDeviceIndependentColor -dDownsampleColorImages=true -dDownsampleGrayImages=true -dDownsampleMonoImages=true -dMaxSubsetPct=100 -dSubsetFonts=true -dEmbedAllFonts=true -dOptimize=true -dUseFlateCompression=true -dNOPAUSE -dBATCH -sDEVICE=pdfwrite" |
tvercaut
/ fortunegenerator.html
Last active
January 4, 2019 18:04
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| <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> | |
| <html> | |
| <head> | |
| <!-- Get jquery --> | |
| <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> | |
| <link href="https://fonts.googleapis.com/css?family=Lato%3A300%2C300italic%2C400%2C400italic%2C700%2C700italic" rel="stylesheet" type="text/css"/> | |
| <link href="https://fonts.googleapis.com/css?family=Roboto:300,400,500,700|Source+Code+Pro:400,700" rel="stylesheet" type="text/css"> | |
| <link rel="stylesheet" href="https://www.gstatic.com/_/atari/_/ss/k=atari.vw.-2q1obhhypir7.L.W.O/d=1/rs=AGEqA5mToJSdsBqoIabxpABkzJkjFu3hJg"/> |
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