NON COMMERCIAL example of a video convert tool for the .playvid tool

convert.py

#!/usr/bin/env python3

# NON COMMERCIAL example of a video convert tool for the .playvid tool
#
# Version: 4

# Changelog
#  V1 first public release
#  V2 Correct RGB 332 colourspace forced
#  V3 Handle off-by-one errors when audio is one frame longer than video length
#  V4 Delete's the BMP files as it goes, added changelog

import os
import sys
import math

file_name = sys.argv[1]
print (f"Conerting {file_name}")
print("   AUDIO")
# Step #1: Generate audio
os.system("ffmpeg -y -i "+file_name+".mp4  -f u8 -ar 15550 "+file_name+".pcm")
print("   FRAMES")
# Step #2 Generate BMPs, crunched to the next palette
os.system("ffmpeg -y -i "+file_name+".mp4  -vsync cfr -r 16.666666 -vf \"transpose=2,scale=w=240:h=320:sws_dither=auto\" -pix_fmt bgr8 \""+file_name+"_%d.bmp\"")

file_stats = os.stat(file_name+".pcm")

print(f'File Size in Bytes is {file_stats.st_size}')
file_frames = math.floor(file_stats.st_size / (933 * 2))
print(f'Total Framecount is {file_frames}')

video_file = open(file_name+".bin","wb")
audio_file = open(file_name+".pcm","rb")

# Pad audio samples to a round 2k
audio_padding = bytearray([68, 68, 82, 83, 127, 50,50] * 26)

# Encode each frame individually, packing the pixels down to the default next palette. Other colour-formats exist in the player, but this encoder targets the "default" palette only
for file_number in range(1,file_frames+1):
    print(f"Frame {file_number}")
    
    # Open preprocessed bitmap, generated by #2 above
    bmp = open(file_name+"_"+str(file_number)+".bmp", 'rb')

    # Read one frame of audio, x2 for left and right
    audio_data = audio_file.read(933*2)
    
    # output samples, and pad them to 2k
    video_file.write(audio_data)
    video_file.write(audio_padding)
    
    bmp_header = bmp.read(54)
    bmp_palette = bmp.read(1024)
    
    bmp_frame = bmp.read(76800)
    video_frame = bytearray([0]*76800)
   
    for bmp_pixel in range(76800):
        palette_index = (bmp_frame[bmp_pixel])*4
        
        red = ((bmp_palette[palette_index+2]) >>5)<<5
        green = ((bmp_palette[palette_index+1]) >>5)<<2
        blue = ((bmp_palette[palette_index]) >>6)

        video_frame[bmp_pixel] = red+green+blue


    video_file.write(video_frame)
    
    bmp.close()

    # Delete the encoded BMP file from the disk
    os.unlink(file_name+"_"+str(file_number)+".bmp")

audio_file.close()