| # Replace the parameters on capital letters | |
| ffmpeg -y -ss 30 -t 3 -i EXAMPLE.mp4 -vf fps=10,scale=320:-1:flags=lanczos,palettegen palette.png | |
| ffmpeg -ss START_TIME -t DURATION -i EXAMPLE.mp4 -i palette.png -filter_complex "fps=10,scale=320:-1:flags=lanczos[x];[x][1:v]paletteuse" OUTPUT.gif |
Magic words:
psql -U postgresSome interesting flags (to see all, use -h or --help depending on your psql version):
-E: will describe the underlaying queries of the \ commands (cool for learning!)-l: psql will list all databases and then exit (useful if the user you connect with doesn't has a default database, like at AWS RDS)
| Latency Comparison Numbers (~2012) | |
| ---------------------------------- | |
| L1 cache reference 0.5 ns | |
| Branch mispredict 5 ns | |
| L2 cache reference 7 ns 14x L1 cache | |
| Mutex lock/unlock 25 ns | |
| Main memory reference 100 ns 20x L2 cache, 200x L1 cache | |
| Compress 1K bytes with Zippy 3,000 ns 3 us | |
| Send 1K bytes over 1 Gbps network 10,000 ns 10 us | |
| Read 4K randomly from SSD* 150,000 ns 150 us ~1GB/sec SSD |