I am using the following command to encode an AVI to an H264 video for use in an HTML5 video tag:
ffmpeg -y -i "test.avi" -vcodec libx264 -vpre slow -vpre baseline -g 30 "out.mp4"
And this works just fine. But I also want to create a placeholder video (long story) from a single still image, so I do this:
ffmpeg -y -i "test.jpg" -vcodec libx264 -vpre slow -vpre baseline -g 30 "out.mp4"
And this doesn't work. What gives?
EDIT: After trying LordNeckbeards answer, here is my full output: http://pastebin.com/axhKpkLx
Example for a 10 second output:
ffmpeg -loop 1 -framerate 24 -i input.jpg -c:v libx264 -preset slow -tune stillimage -crf 24 -vf format=yuv420p -t 10 -movflags +faststart output.mp4
Same thing but with audio. The output duration will match the input audio duration:
ffmpeg -loop 1 -framerate 24 -i input.jpg -i audio.mp3 -c:v libx264 -preset slow -tune stillimage -crf 24 -vf format=yuv420p -c:a aac -shortest -movflags +faststart output.mp4
-loop 1 loops the image input.
-framerate sets the frame rate of the image input. Default is 25. Some players have issues with low frame rates so a value over 6 or so is recommended.
-i input.jpg the input.
-c:v libx264 the H.264 video encoder.
-preset x264 encoding preset. Use the slowest one you can.
-tune x264 tuning for various adjustments to fit specific situations.
-crf for quality. A lower value results in higher quality. Use the highest value that still provides an acceptable quality to you. Default is 23.
-vf format=yuv420p outputs the pixel format as yuv420p. This ensures the output uses a widely acceptable chroma sub-sampling scheme. Recommended for libx264 when encoding from images.
-c:a aac the AAC audio encoder. If your input is already AAC or M4A then use -c:a copy instead to stream copy instead of re-encode.
-t 10 (in the first example) makes a 10 second output. Needed because the image is looping indefinitely.
-shortest (in the second example) makes the output the same duration as the shortest input. In this case it is the audio since the image is looping indefinitely.
-movflags +faststart relocates the moov atom to the beginning of the file after encoding is finished. Allows playback to begin faster in progressive download playing; otherwise the whole video must be downloaded before playing.
-profile:v main (optional) some devices can't handle High profile.
See FFmpeg Wiki: H.264 for more info.
Related
I wanted to encode a video file which was initially encoded by a libx264 encoder on a non gpu machine with ultrafast preset and crf 23 , i typically re-encode it with preset medium and get a good compression but the process is very slow , so i am considering a gpu based solution
my current command to use ffmpeg on a nvidia turing gpu
ffmpeg -y -vsync passthrough -hwaccel cuda -i a.mp4 -max_muxing_queue_size 9999 -pix_fmt yuv420p -c:v h264_nvenc -preset medium -tune ll -b:v 4M -bufsize 4M -maxrate 10M -qmin 0 b.mp4
usual command i use to do the same
ffmpeg -i a.mp4 -max_muxing_queue_size 9999 -pix_fmt yuv420p -c:v libx264 -preset medium b.mp4
enter code here
How can i make this command do a better job at reducing file size , i am okay to compromise on the quality of the video for a good reduction in size
I would highly recommend reading this H.264 Video Encoding Guide
On the surface, these variants can help you:
Decrease your bitrate
Add -cq option with suitable value 0-51 (-cq for h264_nvenc is pretty the same as -crf for libx264)
Change -tune option value to hq
Try two-pass encoding (if you know desired output file size), but here is very low benefit
If you struggle with available options for h264_nvenc you can see the whole list of them by executing following command:
ffmpeg -hide_banner -h encoder=h264_nvenc
Most of them are self descriptive or similar from libx264
I can't seem to understand how to make the conversion lossless (or at least visually lossless)? The outputs have some fast moving parts at times, and the output would become blocky; I would like to keep it as lossless as possible, while still maintaining some compression. What would I have to tweak at the command line? Thanks you~
ffmpeg -c:v libvpx-vp9 -i in.webm -c:v libvpx -vf scale=400:416,hue=h=45:s=1 -auto-alt-ref 0 out.webm
According to FFmpeg Wiki: VP9, "two-pass is the recommended encoding method for libvpx-vp9 as some quality-enhancing encoder features are only available in 2-pass mode". Example of your command:
ffmpeg -c:v libvpx-vp9 -i in.webm -c:v libvpx-vp9 -vf scale=400:416,hue=h=45:s=1 -b:v 0 -crf 30 -pass 1 -an -f null /dev/null
ffmpeg -c:v libvpx-vp9 -i in.webm -c:v libvpx-vp9 -vf scale=400:416,hue=h=45:s=1 -b:v 0 -crf 30 -pass 2 -c:a copy output.webm
The CRF value can be from 0–63. Lower values mean better quality. Recommended values range from 15–35, with 31 being recommended for 1080p HD video. For more info see Google - Getting Started with VP9.
I am trying to get ffmpeg to work as expected however I am having all kinds of trouble getting it to work.
I need to output a webm and h264 for web play. However, the command I am using, while it used to work a few years ago, does not work at all now.
Both my webm and h264 do not have audio, and neither will play in any browser.
My command for webm is:
ffmpeg -y -i "$KMVAR_File" -c:v libvpx -crf 24 -b:v 1000k -vf scale=720:-2 -c:a libvorbis "$KMVAR_webmPath"
and my command for mp4 is:
ffmpeg -y -i "$KMVAR_File" -c:v libx264 -pix_fmt yuv420p -profile:v baseline -level 3.0 -crf 32 -b:v 1M -minrate 1M -maxrate 1M -bufsize 2M -vf scale=720:-2 -c:a aac -strict experimental -movflags +faststart "$KMVAR_mp4Path"
When playing with multiple audio, downmixing or extracting, there's no "one size fit all" solution with ffmpeg.
Look at https://trac.ffmpeg.org/wiki/AudioChannelManipulation as it provides multiple possible solution to your problem.
(I usually go with the pan filter : not the easiest to use, but more powerful than the map_channel approach)
Help me find a command or script that will convert any video to 16:9, h264 and ~2500kbps. I have a server where people upload videos of different quality, size and length. It can be either 640x480 or 1216x2160. Ultimately, I need to get any resolution to 16:9 (with black borders, if needs) and bitrate without visible loss of quality, which will be acceptable for online broadcasting.
I have this command, but it does not check the resolution of the video. And if the video was 560x448 1000kbps and 700mb, then after conversion it will be 1280x720 3000kbps and 1.5gb, that's not right.
ffmpeg -i 5.avi -vcodec libx264 -crf 23 -preset veryfast -vf scale=1280:720:force_original_aspect_ratio=decrease,pad=1280:720:(ow-iw)/2:(oh-ih)/2,setsar=1 -tune zerolatency highoutput.mp4
Please try the following as a starting point:
ffmpeg -i "5.avi" -vcodec libx264 -crf 23 -vf "scale=w=trunc(ih*dar/2)*2:h=trunc(ih/2)*2, setsar=1/1, scale=w=1920:h=1080:force_original_aspect_ratio=1, pad=w=1920:h=1080:x=(ow-iw)/2:y=(oh-ih)/2:color=#000000" "output.mp4"
Please tweak the crf value depending on the picture quality.
Use
-vf scale=iw*sar:ih,setsar=1,pad='max(iw+mod(iw,2),2*trunc(ih*16/9/2))':'max(ih+mod(ih,2),2*trunc(iw*9/16/2))':-1:-1
I am trying to do three tasks with FFMPEG
Crop a video without losing quality
Resize (upscale) the cropped video with good quality
Cut specific part of a the upscaled vided without losing quality
Here are the command line I use:
to crop: video og.mp4 to video og1.mp4
ffmpeg -i og.mp4 -vf "crop=1330:615:22:120" -c:v libx264 -crf 1 -preset veryslow -c:a copy og1.mp4
to resize: video og1.mp4 (converted above) to video og2.mp4
ffmpeg -i og1.mp4 -vf scale=1920:-1 -c:v libx264 -crf 1 -preset veryslow -c:a copy og2.mp4
to cut: video og2.mp4 (converted above) to og3.mp4
ffmpeg -i og2.mp4 -ss 00:00:08.190 -t 00:00:11.680 -c:v libx264 -crf 1 -preset veryslow -c:a copy og3.mp4
I want to achieve highest quality of 1920 width video (irrespective of height and size of the file)
Is there a way to get the above tasks in one command or shorter time with best quality?
Also advice if there is a better command or parameters to be used.
Thanks
You can combine all commands by using a single filterchain, and adding the trim as well
ffmpeg -ss 8.190 -t 11.680 -i og.mp4 -vf "crop=1330:615:22:120,scale=1920:-2" -c:v libx264 -crf 1 -c:a copy og1.mp4
With crf 1, a slow preset is unnecessary.