Calculates average bitrate of a video file by looking at size of each frame. Uses ffprobe, sed and awk

calcavgbitrate.sh

#!/bin/bash

# Calculates average bitrate of a video file by looking at size of each frame. Uses ffprobe, sed and awk

if [ -z "$1" ]; then
    echo "Error: No input video file specified"
    exit 1
fi

echo "Estimating bitrate statistics for $1..." ; ffprobe -show_frames -loglevel error $1 | \
    grep -A 20 media_type=video | \
    grep "pkt_size\|pkt_duration_time"| \
    sed 'N;s/\n/ /' | \
    sed 's/pkt_duration_time=\([0-9\.]*\) pkt_size=\([0-9\.]*\)/\1 \2/' | \
    awk 'BEGIN {
            lines=0;
            totalBits=0;
            # total nr of frames for logging, not used for calculation
            totalFrameTime=0
        }
        {
            # bytes per frame ($2) * 8 = bits per frame
            # bits per frame / frame length ($1) = bits per second
            totalBits += $2 * 8 / $1;
            totalFrameTime += $1;
            lines++
        }
        END {
            printf("Total Mbits: %8.2f, average frametime: %3.3f ms\nAverage bitrate: %4.3f Mbit/s\n", totalBits/1000000, totalFrameTime/lines, totalBits/lines/1000000)
        }'