All Questions
Tagged with ffmpeg compression
80
questions
1
vote
1
answer
2k
views
What does an encoding speed of "[number] X" mean when using ffmpeg?
When I run ffmpeg using
ffmpeg -i input.wav -c:a flac -compression_level 12 output.flac
I get
this result.
Meanwhile if I run it using
ffmpeg -i input.wav output.flac
which gives you the ...
- 11
1
vote
1
answer
1k
views
ffmpeg (libmp3lame) doesn't compress to correct bitrate - just Audio
I have some uncompressed WAV files that I wan't to compress to a CBR of 8kb/s - which the documentation says is possible by using -b:a 8k in the ffmpeg command.
however when I run it on my raw audio ...
- 111
0
votes
0
answers
4k
views
Higher quality of JPEG frames extracted with FFMPEG from MP4 video
I got a 4k mp4 video file and my goal is to extract the individual frames. Unfortunately, the video is quite big ~10GB and storing all the frames lossless (e.g. using png, results in 12MB per frame) ...
- 101
-1
votes
1
answer
2k
views
Choosing compression method and settings for mp4 files
I've got a hard drive filled up with videos, and want them to take up as little space as possible.
Video encoding:
Around 20000 kbps datarate and bitrate
30 frames/second
H.264 AVC
Audio ...
17
votes
1
answer
26k
views
Producing lossless video from set of .png images using ffmpeg
I have a set of .png images that I would like to animate into a movie using ffmpeg on macOS, but when I look at the video produced the quality is always compressed and the resulting video has ...
- 273
17
votes
4
answers
15k
views
Can compressed videos be decoded back to their uncompresed original format?
The following is mentioned in the ffmpeg documentation.
ffmpeg calls the libavformat library (containing demuxers) to read
input files and get packets containing encoded data from them...
...
- 319
0
votes
1
answer
447
views
ffmpeg transcode twice compress further?
I have a collection of avi videos (say A).
I first convert them into MPEG4 Part2 (say B) using ffmpeg -i ${inname} -vf scale=340:256,setsar=1:1 -q:v 1 -c:v mpeg4 -g 12 -f rawvideo ${outname}. The ...
- 1
1
vote
1
answer
6k
views
libx265 & ffmpeg: the better compression, the larger files?
Trying to squeeze the last bit, I made the finding, that my files get larger then smaller. Unfortunately I must have misinterpreted some parameters.
Maybe you can help me.
The reference is -preset ...
- 121
0
votes
1
answer
413
views
Largest possible compression for big video files using FFmpeg
I've been fascinated by a copy of “The Emoji Movie” being compressed to 45 megabytes, and was wondering how would I go about achieving such compression to very large movies. Of course, if some ...
0
votes
1
answer
107
views
FFMPEG: H265, -Preset Options Are Out Of Order
With H264, the higher the preset (ex., -preset 9), the slower yet better the compression (the wait is long long but the file size is small). However, with H265, I found that -preset 2 gets the best ...
- 451
9
votes
1
answer
34k
views
What archive compression makes .mp4 files the smallest?
Is there an archive-based compression format that is known to make the smallest .mp4 videos?
I did a test 1080p 0:12 duration video with the only archival formats I know about:
(python3) Joshs-MBP:...
- 285
1
vote
1
answer
515
views
Exiftool's "-tagsfromfile" does not help recover all metadata (#iphone)
This is a long standing practical problem (more than one year). I always want to finish it, but every time I tried I failed. I have consulted several threads for it.
I have a bunch of daily-life ...
- 121
4
votes
1
answer
5k
views
Best image compression for low bit depth, grayscale images?
I am trying to compress many (up to 2,500) small (300x200 px) grayscale images so the file size is as small as possible. Currently, my bit depth is 4 (16 shades of gray). Image source is surveillance ...
- 41
1
vote
1
answer
859
views
Does an FFmpeg preset have any use if I'm using -crf 0?
I'm encoding a video for upload to YouTube and Facebook using libx264 and setting -crf 0.
Is there any benefit to using a preset as well? My understanding is that the preset affects encoding speed/...
- 13
12
votes
1
answer
5k
views
Using a lossless video codec for archiving (monochrome) scientific video data
Basic question: what is a suitable codec for storing/archiving scientific video data in a lossless manner?
I am trying to help my research group out with storing/archiving some videos recorded with a ...
- 123