I am using FFMPEG to convert uploaded videos to .flv, after conversion the flv video doesn't have information about it's duration. So the user cannot rewind/forward, replay or see a specific part of it. The code is as follows:
"ffmpeg -i $srcfile_path -s 320x240 -ar 44100 -b 2048k -r 12 $desfilepath";
Please help. Thanks in advance.
I ran the following command and it worked.
"ffmpeg -i $srcfile_path -f flv - | flvtool2 -U stdin $desfilepath"
This requires flvtool installed on your system. I am using an FFMPEG and FLVTOOL2 enabled server, so it worked.
That's very strange, I have been using ffmpeg to convert videos from one format to another without any issues. See example below:
ffmpeg -i input.avi -b:a 192K -b:v 2400 -s hd720 -c:v mpeg2video output.mpg
I am sure you know the syntax.
Related
I want to capture video+audio from directshow device like webcam and stream it to RTMP server. This part no problem. But the problem is that I want to be able to see the preview of it. After a lot of search someone said pipe the input using tee muxer to ffplay. but I couldn't make it work. Here is my code for streaming to rtmp server. how should I change it?
ffmpeg -rtbufsize 8196k -framerate 25 -f dshow -i video="Microsoft® LifeCam Studio(TM)":audio="Desktop Microphone (Microsoft® LifeCam Studio(TM))" -vcodec libx264 -acodec aac -strict -2 -b:v 1024k -b:a 128k -ar 48000 -s 720x576 -f flv "rtmp://ip-address-of-my-server/live/out"
Here is the final code I used and it works.
ffmpeg -rtbufsize 8196k -framerate 25 -f dshow -i video="Microsoft® LifeCam Studio(TM)":audio="Desktop Microphone (Microsoft® LifeCam Studio(TM))" -vcodec libx264 -acodec aac -strict -2 -f tee -map 0:v -map 0:a "[f=flv]rtmp://ip-address-and-path|[f=nut]pipe:" | ffplay pipe:
The core command for those running ffmpeg on a Unix-compatible system (e.g. MacOS, BSD and GNU-Linux) is really quite simple. It's to redirect or to "pipe" one of the outputs of ffmpeg to ffplay. The main problem here is that ffmpeg cannot autodetect the media format (or container) if the output doesn't have a recognizable file extension such as .avi or .mkv.
Therefore you should specify the format with the option -f. You can list the available choices for option -f with the ffmpeg -formats command.
In the following GNU/Linux command example, we record from an input source named /dev/video0 (possibly a webcam). The input source can also be a regular file.
ffmpeg -i /dev/video0 -f matroska - filename.mkv | ffplay -i -
A less ambiguous way of writing this for non-Unix users would be to use the special output specifier pipe.
ffmpeg -i /dev/video0 -f matroska pipe:1 filename.mkv | ffplay -i pipe:0
The above commands should be enough to produce a preview. But to make sure that you get the video and audio quality you want, you also need to specify, among other things, the audio and video codecs.
ffmpeg -i /dev/video -c:v copy -c:a copy -f matroska - filename.mkv | ffplay -i -
If you choose a slow codec like Google's AV1, you'd still get a preview, but one that stutters.
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
I'm trying to convert a gif file to webm file using the below which works fine however I’m wondering is it also possible to reverse it as well using ffmpeg or would I need to reverse it using imagemagick first then cover it using ffmpeg
ffmpeg -i your_gif.gif -c:v libvpx -crf 12 -b:v 500K output.webm
Any help is appreciated
The script posted here might help you.
This one seems to be in bash but ripping the commands should work on Windows as well.
https://github.com/WhatIsThisImNotGoodWithComputers/ffmpeg-webm-scripts
These are the relevant lines of code (note that they need to edited for your setup):
ffmpeg -i "${INPUT_FILE}" -ss $START_TIME -to $TO_TIME -an -qscale 1 $TEMP_FOLDER/%06d.jpg
cat $(ls -r $TEMP_FOLDER/*jpg) | ffmpeg -f image2pipe -vcodec mjpeg -r 25 -i - -c:v libvpx -crf 20 -b:v $FRAMERATE $CROPSCALE -threads 0 -an $OUTPUT_FILE
You basically have to convert all stills to jpgs and then back into webm, but in reverse order.
From ffmpeg --help, you can see what codecs ffmpeg supports with ffmpeg -codecs. ffmpeg -codecs|grep -i gif on mine says it supports gif.
ffmpeg checks extensions to get file type if you don't override,
ffmpeg -i onoz.webm onoz.gif
does the trick just fine.
I am using ffmpeg to convert any avi/wmv videos to flv.
My trouble is that the flv result is quite poor: it gives me big pixelitaed boxes.
I tried to use some -b parameters with no good results:
ffmpeg -i 1268459654.wmv -ar 22050 -ab 32 -f flv -s 640x480 x.flv
ffmpeg -i 1268459654.wmv -ar 22050 -ab 32 -f flv -s 640x480 -b 500k x.f4v
I also tried
ffmpeg -i 1268459654.wmv -vcodec libx264 -s 360x240 x.mp4
ans got: "Unknown encoder 'libx264'"
Any solution for that ?
libx264 does not come pre-installed (licensing issues I believe) if you've downloaded it via yum/RPM. You'll need to download the source and compile it yourself and specify libx264. Here's a command line I've used in the past with decent results, and I would consider the MP4 Container over the dated, FLV format personally.
ffmpeg -i (file) -acodec libfaac -ab 44k -vcodec libx264 -vpre normal -crf 30 -threads 0
Make note of the "-vpre normal", as you should have some presets available under:
/usr/share/ffmpeg/libx264-normal.ffpreset or similar.
More details on compiling from source.
I use in command line for ffmpeg
-i Input.flv -vcodec h263 -b 256k -r 15 -s 320x240 -acodec libopencore_amrnb \
-ab 7.4k -ar 8000 -ac 1 -f 3gp Output.3gp
The result is audio-only, without video. But when the 176x144, it works great.
What's wrong in using of frame size (320x240)? And what is the solution?
Are you sure there is no video in the resulting Output.3gp file? Is it possible that the end device does not support 320x240?
It would help significantly if you were to include the entire FFmpeg output in your question.