How add scale in my ffmpeg command - ffmpeg

i want convert video from any format to mp4. so i am using command:
ffmpeg -i ttt.mp4 -vcodec copy -acodec copy test.mp4
this is working perftectly but now i also add scale in this -s 320:240.
There also many other command for convert LIKE :
ffmpeg -i inputfile.avi -s 320x240 outputfile.avi
but after convert by this command video not play in html5 player
BUT this is not working so tell me in my command how i add scale;
So please provide me solution for this .
Thanks in advance.

You have several problems:
In your command, you have -vcodec copy you cannot scale video without reencoding.
In the command you randomly found on the Internet, they are using AVI, which is not HTML5-compatible.
What you should do is:
ffmpeg -i INPUT -s 320x240 -acodec copy OUT.mp4

Adding to Timothy_G:
Video copy will ignore the video filter chain of ffmpeg, so no scaling is available (man ffmpeg is a great source of information that you will not find on Google). Notice that once you start decoding-filtering-encoding (i.e., no copy) the process will be much slower (x100 time slower or even more). The libx264 is recommended if you want compatibility with all browsers.
$ ffmpeg -i INPUT -s 320x240 -threads 4 -c:a copy -c:v libx264 OUT.mp4
vp9 will provide nearly 50% extra bandwidth saving, but only for supported browsers (Firefox/Chrome), and the encoding will much slower compared to libx264 (that itself is much slower that v:c copy):
$ ffmpeg -i INPUT -s 320x240 -c:a copy -c:v vp9 OUT.webm
Notice that there is a set of formats (containers) accepted by browsers (most admit mp4, some also webm, ...) and for each format there is a set of audio/video codecs accepted. For example you can use mp3 or aac with an mp4 file (container), but not with webm files.
http://en.wikipedia.org/wiki/HTML5_video#Supported_video_formats

Related

FFMPEG reduce fps for live h264 stream with direct copy

I found different articles on changing the fps with ffmpeg but none of them is matching for my exact purposes.
There is an ffmpeg command like below:
ffmpeg -i RTSPCAMERAPRODUCEH264 -c:v copy -an -movflags +frag_keyframe+empty_moov -f mp4
This will remux my camerastream to fragmented mp4 perfectly.
Is there a way to force ffmpeg to lower the FPS to save bandwidth?
I.e. camera streams 30fps, it needs 1Mbps for fmp4 (sample numbers!):
I'd like to know if it's possible to lower the FPS and get an output stream for which 500kbps (50% of original is enough) without re-encoding.
ffmpeg -r 1 -i RTSPCAMERAPRODUCEH264 -c:v copy -an -movflags +frag_keyframe+empty_moov -f mp4
and
ffmpeg -i RTSPCAMERAPRODUCEH264 -c:v copy -an -movflags +frag_keyframe+empty_moov -r 1 -f mp4
do not seem to work.
A temporally coded video stream (like one with H264 codec) cannot arbitrarily drop intermediate packets, so this is not possible. Only whole or trailing part of GOPs may be dropped.

Ffmpeg makes audio longer when changing bitrate

I've been using ffmpeg convert audio from one format to another and to change audio's bitrate. When I try to convert aac audio to mp3 audio using the command:
ffmpeg -i SomeAudio.aac -c:a mp3 -b:a 128k SomeOutputPath.mp3
everything works correctly and output audio is of the same length as the input audio (6 minutes, 15 seconds).
However, when I try converting it to aac audio using a similar command:
ffmpeg -i SomeAudio.aac -c:a aac -b:a 128k SomeOutputPath.aac
it makes the output audio longer (around 10 minutes). I have tried specifying output length but that still makes the video longer, it just cuts of part of the audio:
ffmpeg -i SomeAudio.aac -c:a aac -b:a 128k -t 00:06:15 SomeOutputPath.aac
Here is a link to the screenshot:
My suspicion is that message "Estimating duration from bitrate, this may be innacurate" (the one in the screenshot) is the root of my problem but I just haven't been able to find any useful information about it on the web.
Thanks a lot for any help in advance :)
The duration shown for raw AAC is a guess because it does not contain duration info. You can find the actual duration with:
ffmpeg -i input.aac -f null -
Or a faster, "close enough" method:
ffmpeg -i input.aac -c copy -f null -
Workaround is to remux to M4A:
ffmpeg -i input.aac -c copy output.m4a

How to wrap H264 into a mp4 container?

I have a program generating a bunch of raw H264 frames and would like to place that into a mp4 container for streaming.
Anyone know how to do that?
I was thinking I'd use ffmpeg however, this needs to be used commercially and it seems like ffmpeg can only do this through it's x264 library... which uses a GPL license.
Thank you!
If you're looking for the FFMPEG command line to do that, then try the following:
ffmpeg -i "source.h264" -c:v copy -f mp4 "myOutputFile.mp4"
If you have a separate audio file you can add it too:
ffmpeg -i "source.h264" -i "myAudio" -c:v copy -c:a copy -f mp4 "myOutputFile.mp4"
If your audio needs to be encoded as well (for instance codec AAC-LC, bitrate 256kbps):
ffmpeg -i "source.h264" -i "myAudio" -c:v copy -c:a aac -b:a 256k -strict -2 -f mp4 "myOutputFile.mp4"
libmp4v2 is under the MPL and can be used as part of a larger work commercially. It is much lighter than libavformat also.

Converted mp4 h264 baseline format loads long time

I have converted my video to mp4 x264 baseline format and it works fine with all pc/mobile phones , the problem is it takes long time to load the video while googling came to know that ffmpeg converts and sets the index file at the eof the video so it loads to the end to read and then plays the video, So any advices would be appreciatable to cut short the loading time.
Note:tryied out QT index swapper2 but dint give much difference , please advice .
this is the cmd i used to convert -
ffmpeg -i … -c:v libx264 -profile:v baseline -level 1 …
Thanks for your time .
You have several options to relocate the moov atom so the video can begin playback before it is completely downloaded by the client.
-movflags faststart
The easiest is the option -movflags faststart when re-encoding:
ffmpeg -i input -c:v libx264 -profile:v baseline -movflags faststart output.mp4
If you already encoded your .mp4 file, but simply want to move the atom:
ffmpeg -i input.mp4 -codec copy -movflags faststart output.mp4
You may need to get a more recent ffmpeg version to use this option. See the FFmpeg download page for links to ffmpeg builds for Linux, OS X, and Windows, or you can follow a step-by-step guide to compile ffmpeg.
qt-faststart
Alternatively you can use the qt-faststart tool that comes with the ffmpeg source:
cd ~/ffmpeg/tools
make qt-faststart
./qt-faststart input.mp4 output.mp4
MP4Box
Or you could use MP4Box (usually provided by the gpac package depending on your distro):
MP4Box -add input.mp4 output.mp4
Also See
FFmpeg and x264 Encoding Guide
FFmpeg and AAC Audio Encoding Guide

Using FFMPEG to losslessly convert YUV to another format for editing in Adobe Premier

I have a raw YUV video file that I want to do some basic editing to in Adobe CS6 Premiere, but it won't recognize the file. I thought to use ffmpeg to convert it to something Premiere would take in, but I want this to be lossless because afterwards I will need it in YUV format again. I thought of avi, mov, and prores but I can't seem to figure out the proper command line to ffmpeg and how to ensure it is lossless.
Thanks for your help.
Yes, this is possible. It is normal that you can't open that raw video file since it is just raw data in one giant file, without any headers. So Adobe Premiere doesn't know what the size is, what framerate ect.
First make sure you downloaded the FFmpeg command line tool. Then after installing you can start converting by running a command with parameters. There are some parameters you have to fill in yourself before starting to convert:
What type of the YUV pixel format are you using? The most common format is YUV4:2:0 planar 8-bit (YUV420p). You can type ffmpeg -pix_fmts to get a list of all available formats.
What is the framerate? In my example I will use -r 25 fps.
What encoder do you want to use? The libx264 (H.264) encoder is a great one for lossless compression.
What is your framesize? In my example I will use -s 1920x1080
Then we get this command to do your compression.
ffmpeg -f rawvideo -vcodec rawvideo -s 1920x1080 -r 25 -pix_fmt yuv420p -i inputfile.yuv -c:v libx264 -preset ultrafast -qp 0 output.mp4
A little explanation of all other parameters:
With -f rawvideo you set the input format to a raw video container
With -vcodec rawvideo you set the input file as not compressed
With -i inputfile.yuv you set your input file
With -c:v libx264 you set the encoder to encode the video to libx264.
The -preset ultrafast setting is only speeding up the compression so your file size will be bigger than setting it to veryslow.
With -qp 0 you set the maximum quality. 0 is best, 51 is worst quality in our example.
Then output.mp4 is your new container to store your data in.
After you are done in Adobe Premiere, you can convert it back to a YUV file by inverting allmost all parameters. FFmpeg recognizes what's inside the mp4 container, so you don't need to provide parameters for the input.
ffmpeg -i input.mp4 -f rawvideo -vcodec rawvideo -pix_fmt yuv420p -s 1920x1080 -r 25 rawvideo.yuv

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