yohhoy

AV1 coding scheme

• Arithmetic coding
  • multi-symbols (up to 16 values)
  • Coefficients coding: lv_map
  • CDF: Cumulative distribution function
    • CDF update (at the end of frame)
    • CDF update (adaptive per symbol)
• Image blocking

yohhoy

#include <chrono>
#include <iostream>

using namespace std::chrono;

year_month_day premium_friday(year y, month m)
{
  return sys_days{y/m/Friday[last]};
}

yohhoy

.LC0:
        .string "ABCDEFGHIJKLMNOP"
main:
        subq    $8, %rsp
        movl    $16, %edi
        movl    $.LC0, %esi
        call    sink(std::basic_string_view<char, std::char_traits<char> >)
        movl    $16, %edi
        movl    $.LC0, %esi
        call    sink(std::basic_string_view<char, std::char_traits<char> >)

yohhoy

*********** NAL UNIT (VPS) ***********
       0  forbidden_zero_bit                                 u(1)  : 0
       1  nal_unit_type                                      u(6)  : 32
       2  nuh_layer_id                                       u(6)  : 0
       3  nuh_temporal_id_plus1                              u(3)  : 1
=========== Video Parameter Set     ===========
       4  vps_video_parameter_set_id                         u(4)  : 0
       5  vps_base_layer_internal_flag                       u(1)  : 1
       6  vps_base_layer_available_flag                      u(1)  : 1
       7  vps_max_layers_minus1                              u(6)  : 0

yohhoy

/*
 * heic2hevc.cpp -- convert HEIC file to H.265 bitstream(Annex.B)
 * Copyright(c) 2017 yohhoy
 *
 * depends https://github.com/nokiatech/heif
 */
#include <iostream>
#include "hevcimagefilereader.hpp"

int extract(const char* srcfile, const char* dstfile)

yohhoy

package jp.yohhoy.hevcdec;

import android.app.Activity;
import android.content.Context;
import android.media.MediaCodec;
import android.media.MediaFormat;
import android.os.Bundle;
import android.util.Log;
import android.util.Size;
import android.view.Surface;

yohhoy

#!/usr/bin/env python3
import math
import sys
from operator import itemgetter

pgmfile = sys.argv[1]

with open(pgmfile, 'rb') as f:
    # parse PGM header
    f.readline()

yohhoy

const char *n2b(unsigned n, int l) {
    static char buf[32+1];
    for (int i = 0; i < l; i++) {
        buf[l - i - 1] = (n & 1) ? '1': '0';
        n >>= 1;
    }
    buf[l] = '\0';
    return buf;
}

yohhoy

#!/bin/bash

LIBJPEG=/usr/local/opt/jpeg/bin/cjpeg
MOZJPEG=/usr/local/opt/mozjpeg/bin/cjpeg
LIBJEPG_OPTS=""
MOZJPEG_OPTS=""
QRANGE=`seq 80 100`

# ImageMagick
IDENTIFY=/usr/local/opt/imagemagick/bin/identify

yohhoy

#!/usr/bin/env python3
from http import server

server_address = ('localhost', 8080)

class Handler(server.SimpleHTTPRequestHandler):
    def do_GET(self):
        print('-' * 79)
        super(Handler, self).do_GET()
        print(self.headers)