Reputation: 193302
I am converting MP4 files to WMV with these two rescaling commands:
ffmpeg -i test.mp4 -y -vf scale=-1:360 test1.wmv
ffmpeg -i test.mp4 -y -vf scale=-1:720 test2.wmv
I've also tried:
ffmpeg -g 1 -b 16000k -i test1.mp4 test1.wmv
However, the .wmv files that are produced are "blocky and grainy" as you can see here in a small section of a video screenshot:
These are the sizes:
test.mp4 - 106 MB
test1.wmv - 6 MB
test2.wmv - 16 MB
How can I increase the quality/size of the resulting .wmv files (the size of the .wmv files is of no concern)?
Upvotes: 20
Views: 63612
Reputation: 341
Consider the following command instead (some outdated commands in the final answer section):
ffmpeg -i test.mp4 -c:v wmv2 -b:v 1024k -c:a wmav2 -b:a 192k test1.wmv
REFERENCES
Upvotes: 24
Reputation: 12902
Working answer in 2020, producing an output video without blockiness:
ffmpeg -i input.mp4 -q:v 1 -q:a 1 output.wmv
Upvotes: 10
Reputation: 1
I used this and it turned out quite well
ffmpeg -i "file1.mp4" -q:v 0 -c:v wmv2 -b:v 1024k -c:a wmav2 -b:a 192k test2.wmv
Upvotes: 0
Reputation: 193302
You can simply use the -sameq
parameter ("use same quantizer as source") which produces a much larger sized video file (227 MB) but with excellent quality.
ffmpeg -sameq -i test.mp4 -y -vf scale=-1:360 test1.wmv
In newer versions of ffmpeg flag '-sameq' has been removed. To achieve similar results one should use 'qscale' flag with 0 value:
ffmpeg -sameq -i test.mp4 -qscale 0 -vf scale=-1:360 test1.wmv
Upvotes: 14
Reputation: 16049
One thing I discovered after many frustrating attempts of enhancing the final quality was that if you don't specify a bitrate, it'll use a quite low average. Try -b 1000k for a starting point, and experiment increasing or decreasing it until you reach the desired result. Your file will be quite bigger or smaller, accordingly.
Upvotes: 5