louisswarren

ffmpeg notes

I often want to do something that I believe is non-trivial in ffmpeg, only to discover that it is actually very simple, if only I had known how to do it. I even end up writing wrappers to do simple things, because I keep forgetting what to do. However, this file is my new solution: simply write my own documentation for things I would occasionally like to do.

louisswarren

#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <stdlib.h>

#define POOL_NODE_HEADERS struct pool_node *prev, *next

struct pool_node {
	POOL_NODE_HEADERS;
};

louisswarren

#include <stdio.h>

#define BUF_SZ (1 << 16)

size_t
find_unicode(char *p, size_t n)
{
	size_t i;
	for (i = 0; i < n; ++i) {
		if (p[i] & 128)

louisswarren

CFLAGS += -Ofast

.PHONY: default
default: refactor

.PHONY: refactor
refactor: out.pbm
	sha256sum $< | diff -q goal.sum -

refactor-set: out.pbm

louisswarren

.PHONY: test test-video
test: nz.png
	sxiv $^

test-video: fire
	./fire | mpv --no-correct-pts --fps=30 --scale=oversample -

%.png: %.ppm
	convert $< $@

louisswarren

.PHONY: default
default: keys
	./keys

keys: CFLAGS += -lcrypto

louisswarren

-- Based on https://mazzo.li/epilogue/index.html%3Fp=324.html

data W (S : Set) (P : S → Set) : Set where
  _◁_ : (s : S) → (P s → W S P) → W S P

data 𝟘 : Set where

data 𝟙 : Set where
  ● : 𝟙

louisswarren

.PHONY: default
default: menger8.png

%.png: %.pbm
	convert $^ $@

menger%.pbm: menger
	./$^ $* > $@

menger%.svg: menger.py

louisswarren

#include <stdio.h>
#include <stdlib.h>

struct list_entry {
	struct list_entry *next;
	int value;
};

struct list {
	struct list_entry *head;

louisswarren

#!/usr/bin/env python3

import itertools
import json
import subprocess
import sys
import urllib.request


user = 'louisswarren'