O wiki do FFmpeg diz que a melhor taxa de compactação é a predefinida "muito lenta".
Mas quando estou tentando com meu vídeo, a predefinição veryfastfornece a melhor compactação no meu caso.
A seguir está a saída das minhas amostras:
predefinidoultrafast
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset ultrafast -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-ultrafast.mp4"
frame= 2822
fps= 65
q=-1.0
Lsize=
239118kB
time=00:01:34.18
bitrate=20797.6kbits/s
speed=2.16x
predefinidosuperfast
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset superfast -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-superfast.mp4"
frame= 2822
fps= 63
q=-1.0
Lsize= 150252kB
time=00:01:34.18
bitrate=13068.3kbits/s
speed=2.09x
predefinidoveryfast
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset veryfast -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-veryfast.mp4"
frame= 2822
fps= 62
q=-1.0
Lsize=
115997kB
time=00:01:34.18
bitrate=10089.0kbits/s
speed=2.08x
predefinidofast
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset fast -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-fast.mp4"
frame= 2822
fps= 52
q=-1.0
Lsize=
133773kB
time=00:01:34.18
bitrate=11635.1kbits/s
speed=1.72x
predefinidomedium
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset medium -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-medium.mp4"
frame= 2822
fps= 43
q=-1.0
Lsize=
124154kB
time=00:01:34.18
bitrate=10798.4kbits/s
speed=1.42x
predefinidoslow
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset slow -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-slow.mp4"
frame= 2822
fps= 27
q=-1.0
Lsize= 125262kB
time=00:01:34.18
bitrate=10894.8kbits/s
speed=0.886x
predefinidoslower
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset slower -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-slower.mp4"
frame= 2822
fps= 14
q=-1.0
Lsize= 125061kB
time=00:01:34.18
bitrate=10877.3kbits/s
speed=0.465x
predefinidoveryslow
ffmpeg -y -threads 1 -i "D:\Video\PresentTest\Safari_Dolby_Digital_Plus.m2ts.mp4" -c:v libx264 -preset veryslow -c:a aac -max_muxing_queue_size 1024 "D:\Video\PresentTest\Safari_Dolby_Digital_Plus-veryslow.mp4"
frame= 2822
fps=6.6
q=-1.0
Lsize= 118149kB
time=00:01:34.18
bitrate=10276.2kbits/s
speed=0.221x
Por que a predefinição veryfastgera o arquivo mais compactado em comparação com outras predefinições?
E a perda de vídeo é algo com preset veryfast?