So I have a lot of mp4 files on my computer and I read that QT-FastStart is for moving the metadata from the end of the files to the beginning but how do I use or run it ?
Every time I drag and drop a file into qt-faststart, nothing seems to happen?
I downloaded the 64bit version from here:
https://web.archive.org/web/20140206214912/http://ffmpeg.zeranoe.com/blog/?p=59
Do I need a batch file or something or a specific command line parameter to make it run?
Note, QT-FastStart is described here https://manpages.debian.org/stretch/ffmpeg/qt-faststart.1.en.html
qt-faststart is a utility that rearranges a Quicktime file such that
the moov atom is in front of the data, thus facilitating network
streaming.
It can be used (perhaps among other purposes), for making a sample file when demonstrating an issue. One can take a large file, fix it with QT-FastStart, then use dd to cut a sample. And the sample should play. Whereas if you did dd without doing that then it wouldn't or may not play.
See Neil's answer qt-faststart infile.mp4 outfile.mp4
However, QT-FastStart has now been integrated into ffmpeg.
ffmpeg -i original.3gp -codec copy -movflags +faststart fixed.3gp
List item
simple. in CMD prompt run qt-faststart infile.mp4 outfile.mp4
Related
So I am wanting to create spectrograms using the FFMPEG for thousands of FLAC files in batch.
I am using the following for just one file.
ffmpeg -i audio-in.wav -lavfi showspectrumpic image-out.png
However, I would like to do this for all the files in a certain folder (\Desktop\FLACfiles) and don't want to keep changing the file name and the image output name.
I would like to somehow create a batch script in Windows 10 that automatically creates a spectrogram based on the filename.
I was trying to make it work but I don't have much experience via command line or programming in general. Not sure how to do achieve this.
Simply put, would like to use commands from a working directory containing FLAC files and create a spectrogram for each file matching the filename.
This worked for me using mp3 files but it wasn't fast. Someone may have a better solution. Try this as a bat file.
for %%a in ("*.mp3") do ffmpeg -i "%%a" -lavfi showspectrumpic "%%~na .png"
I have a script that parses a bunch of events from a given movie file and uses the -ss and -endpos flags to play specific portions of the file. Let's say there is one file available. What I want to do is run a chained command like:
mplayer vidfile.mp4 -ss 110 -endpos 5 -fs;mplayer vidfile.mp4 -ss 130
-endpos 9
The idea is to have both sections of the video play in full screen, sequentially. However, there is major flicker between the two videos as it exits to the desktop briefly. (Ubuntu 12.04.)
How can I keep mplayer open or make the switch less jarring? Doing this with 30 clips would give someone a massive headache, and I'd like to see if it can be done this way without writing a script to cut the movies and put them together (which sounds like a nightmare, but if anyone has ideas, please post those in the comments).
Not sure when it was introduced, but mplayer now supports this via the -fixed-vo parameter, from the man page:
-fixed-vo
Enforces a fixed video system for multiple files (one (un)initialization for all files).
Therefore only one window will be opened for all files.
Currently the following drivers are fixed-vo compliant:
gl, gl_tiled, mga, svga, x11, xmga, xv, xvidix and dfbmga.
in my testing this works well with full screen (-fs), no flicker.
example usage:
mplayer -fs -fixed-vo thats_marvellous.mp4 cliff.mp4
I ended up solving it with a quick solution that a friend suggested - take the semi-colon out since mplayer supports multiple files AND flags. (Works for a few files for now, will update if I run into problems down the line.)
mplayer vidfile.mp4 -ss 110 -endpos 5 -fs vidfile.mp4 -ss 130 -endpos 9 -fs
I want to make a "batch" file so to say for some bash commands (convert.sh). I think it would be best to describe the situation. i have a $#!^ ton of mp4 videos that i want converted into mp3's. it would take me an unreasonable amount of time to convert them using ffmpeg -i /root/name\ of\ video.mp4 /name\ of\ video.mp3 for every single video. not to mention the fact that all the file names are long and complicated so typos are a possibility. so i want to know how to make a shell script (for bash) that will take every file with the extension .mp4 and convert it to a .mp3 with the same name one by one. as in it converts one then when it done it moves on to the next one. im using a lightweight version of linux so any 3rd part soft probably wont work so i need to use ffmpeg...
many thanks in advance for any assistance you can provide
PS: i cant seem to get the formatting sytax on the website to work right so if somone can format this for me and maybe post a link to a manual on how it works that would be much appreciated =)
PPS: i understand that questions about using the ffmpeg command should be asked on superuser however since i dont so much have any questions about the specific command and this relates more to scripting a bash file i figure this is the right place
A bash for loop should do it for you in no time:
SRC_DIR=/root
DST_DIR=/somewhereelse
for FILE in ${SRC_DIR}/*.mp4
do
ffmpeg -i "${FILE}" "${DST_DIR}/$(basename \"${FILE}\" .mp4).mp3"
done
Sorry - I don't know the ffmpeg command line options, so I just copied exactly what's in your post.
1) use find:
find . -name \*.mp4 | xargs ./my_recode_script.sh
2) my_recode_script.sh - see this question
so you can easily change the extension for output file name
the rest is trivial scripting job:
ffmpeg -i $name $new_name # in my_recode_script.sh after changing extension
this is enough for one-time script, if you want something reusable, wrap it with yet another script which receive path to dir, extensions from which to which to recode and call other parts :)
What we need to do is either, extract the audio from a group or singular Vob video file and convert it to a .Wav format. Now the process of actually extracting the audio and converting it can be done from a third party application however this application has to be activated from a batch or c# script. The media we are retrieving the vob files from always comes from the CD drive and will always be placed in the same folder location once the conversion is complete.
In shot I need a program or script that can be activated remotely to extract and convert vob files to .WAV.
Any help will be greatly appreciated.
I only install ffmpeg on Windows and put in cmd this command:
ffmpeg -i [VOB_file_route].VOB [WAV_file_output_route].wav
And that's all, just works.
To do somthing like this you will need to use VLC and cmd they work togeather well and will allow you to strip video and audio from a file easily
In my application there are mp3 files located in the bundle (nothing from the web). Some of the mp3 files are original files and some I had edited using simple sound editing software (the ones where you insert a file, cut a slice of it and save it as a new and shorter mp3 file).
I'm using the AVAudioPlayer [initWithData] method.
All the original files (the ones that I hadn't edited and inserted to the bundle as is) are working perfectly and all the ones that were edited are not working at all.
I used 2 different editing software and the outcome is the same.
Anyone had ever encountered that or have any idea what may I done wrong?
Thanks,
Ohad
Converting the mp3 to caf worked for me
as specified here.
see the following:
How do I convert an audio file to the preferred format for iPhone OS?
The preferred full-quality audio format for iPhone OS is 16-bit, little-endian, linear PCM packaged as a CAF file. To convert an audio file to this format, use the afconvert tool at the command line in Mac OS X, as shown in Listing 5.
Listing 5 Converting an audio file to the preferred format for iPhone OS
/usr/bin/afconvert -f caff -d LEI16 {INPUT} {OUTPUT}
To see all the options available for the afconvert tool, enter afconvert -h at the command line.