Ciro Santilli's hardware P51 benchmark by 
Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01
Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01 Ciro Santilli's hardware Dell P2720D by Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01
Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01There are actually two possible definitions for the DFT:
- 1/N, given as "the default" in many sources:
- , known as the "normalized DFT" by some sources: www.dsprelated.com/freebooks/mdft/Normalized_DFT.html, definition which we adopt:
Training machine learning on copyrighted data by Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01
Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01www.threekit.com/blog/gltf-everything-you-need-to-know comparision of several formats
With telescopes however, it is possible. www.quora.com/Can-we-distinguish-individual-stars-in-other-galaxies-or-would-it-be-equivalent-to-say-we-know-there-are-other-forests-of-stars-galaxies-but-we-cant-tell-the-individual-trees-stars-What-is-the-farthest-individual/answer/Jerzy-Micha%C5%82-Pawlak contains an amazing answer that mentions two special cases of the furthest ones:
- gravitational lensing observation
- a star that is far but visible because its light is reflected by a nearby nebulae
But what we can definitely see are globular clusters of galaxies. E.g. the article en.wikipedia.org/wiki/Messier_87 basically gauges the size of galaxies by the number of globular clusters that they contain.
Sample usage by Andy Matuschak (possible coiner): notes.andymatuschak.org/About_these_notes
Previously on EdX: www.edx.org/learn/quantum-physics-mechanics/delft-university-of-technology-topology-in-condensed-matter-tying-quantum-knots "DelftX: Topology in Condensed Matter: Tying Quantum Knots".
But then they regained their sanity and put the source code on GitHub: github.com/topocm/topocm_content and is CC BY-SA.
Wiki without notability requirements by Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01
Ciro Santilli 37 Updated 2025-05-21 +Created 1970-01-01Proponent of evergreen notes.
He's also curious about quantum computing: quantum.country/ like Ciro Santilli. Some crazy overlaps we get.
Filter graphs are a thing of great beauty. What an amazingly obscure domain-specific language, but which can produce striking results with very little!!!
A quick example from stackoverflow.com/questions/59551013/how-to-generate-stereo-sine-wave-using-ffmpeg-with-different-frequencies-for-eac/77730492#77730492 illustrates some of the fundamentals:
ffplay -autoexit -nodisp -f lavfi -i '
sine=frequency=500[a];
sine=frequency=1000[b];
[a][b]amerge, atrim=end=2
' +--------+
[sine=frequency=500]--->[a]-->| |
| amerge |-->[atrim]-->[output]
[sine=frequency=1000]-->[b]-->| |
+--------+So we see the following syntax patterns:
sine,amergeandatrimare filterssine=frequency=500: the first=says "araguments follow";: separates statements[a],[b]: sets the name of an edge,: creates unnamed edge between filters that have one input and one output
A list of all filters can be obtained ith:and parameters for a single filter can be obtained with:Related question: stackoverflow.com/questions/69251087/in-ffmpeg-command-line-how-to-show-all-filter-settings-and-their-parameters-bef
ffmpeg -filtersffmpeg --help filter=sineTODO dump graph to ASCII art? trac.ffmpeg.org/wiki/FilteringGuide#Visualizingfilters mentions a
-dumpgraph option, but haven't managed to use it yet.Bibliography:
- ffmpeg.org/ffmpeg-filters.html official documentation
- trac.ffmpeg.org/wiki/FilteringGuide some handy tips from the FFMpeg Wiki
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