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6

FFmpeg is probably being used more than you believe. I think the BBC uses it for some workflows, there is evidence that Laika and Weta may use it, and there is a fork called FFmbc which is targeted for professional broadcast usage. YouTube probably uses FFmpeg to decode as shown by some unique decoding issues (but this was several years ago that I read ...


5

using the scale filter will do it, but there is a bit more to it. ffmpeg -i input.mov -vf scale=720x406 output.mov will create a movie with the required pixel dimensions, but if you look at the output you'll find that it adds information into the metadata so that it will play back at the same aspect ratio as the original, by using non-square pixels. So ...


5

From http://www.ffmpeg.org/faq.html: If you have large number of pictures to rename, you can use the following command to ease the burden. The command, using the bourne shell syntax, symbolically links all files in the current directory that match *jpg to the ‘/tmp’ directory in the sequence of ‘img001.jpg’, ‘img002.jpg’ and so on. x=1; for i in *jpg; do ...


4

Re-muxing only Use stream copy mode to just re-mux instead of re-encode: ffmpeg -ss 01:07:29 -i input -codec copy -map 0 -to 01:08:05 fight.avi Using -ss as an input option can be faster than using it as an output option, but it may not be as accurate. -codec copy will stream copy (no re-encoding). Default behavior, if -codec copy is omitted, is to ...


3

Apparently by default ffmpeg only copies one stream of each type. To tell it to copy all streams, you need -map 0 So, this does it: ffmpeg -i "concat:a01.mxf|b02.mxf" -y -map 0 -c copy result.mxf


3

One method is to use the overlay video filter. Assuming your video is 640x480, 30 seconds duration, 25 frame rate: ffmpeg -f nullsrc=s=640x480:d=35:r=25 -i video.mp4 -i audio.wav -filter_complex \ "[0:v][1:v]overlay[video]" -map "[video]" -map 2:a -codec:a copy -shortest output.mkv I set the duration of the nullsrc source filter to be 5 seconds longer ...


3

concat filter This method is best if you need to perform additional filtering: Use the trim, atrim, setpts, asetpts, and concat filters: ffmpeg -i input -filter_complex \ "[0:v]trim=60:65,setpts=PTS-STARTPTS[v0]; \ [0:a]atrim=60:65,asetpts=PTS-STARTPTS[a0]; \ [0:v]trim=120:125,setpts=PTS-STARTPTS[v1]; [0:a]atrim=120:125,asetpts=PTS-STARTPTS[a1]; \ ...


3

The main reason is support, usability and control. First, lets clarify that FFMPEG is an encoder, QuickTime Pro is a video utility that happens to include multiple encoders and Final Cut Pro is a non-linear editor and has nothing to do with encoders other than the fact it can output to an encoder (generally QuickTime I believe). For big budget commercial ...


3

There is no "typical" size. It depends entirely on the quality level and level of motion in the video. I could encode ten hours of video where there is no movement with very little space since the compression would work very well. On the other hand, if I had a video where every frame was completely different from the last, it would take a huge amount of ...


3

This depends entirely on what kind of 3d video you want. There are numerous formats for 3d video. Some are as simple as placing the left and right images either side by side or one on top of the other (typically compressing them spatially to still take up the original space, for example 1080p video done like this ends up being wither 540 vertical pixels ...


2

The H.264 standard defines maximum bit rates for 1280x720@30fps as between 14.000 and 42.000 kbit/s, depending on the profile (baseline, main, high etc.). It's even higher for higher frame rates. (http://en.wikipedia.org/wiki/H.264/MPEG-4_AVC) Sony Vegas standard rendering templates use bitrates between 2 and 16 Mbps. Youtube recommends bitrates between ...


2

Option placement matters Is there an option I'm missing? No, but option placement matters. Options before the input apply to the input, and options before the output generally apply to the output. The exception are global options. See the FFmpeg synopsis and FFmpeg description for more details on option placement. Therefore, you must move your -q ...


2

I use it in my professional production chain all the time. Last week I was using it to batch through dozens of videos that needed subtitles burnt-in. It would have taken me weeks of tedious labour with Final Cut, it took me a couple of days burning the srts in with ffmpeg, and I was able to automatically rename the files and compress them for the various ...


2

Depending how the content was made, the banding might be introduced when you're converting your content from RGB colorspace to YUV. You can try to make an h264 while keeping RGB colorspace, although I've read it's not easy. Are you able to use another codec?


2

The bands you're referring to could well just be a limitation of the 8-bit colour space. In theory the way to solve this is to use 10- or 12-bit colour space through every stage from rendering, to editing and mastering, through to output and even in the screen or projector. However your final output is probably going to be displayed in an 8 bits per ...


2

I found a helpful post on stackoverflow that addresses this issue: http://stackoverflow.com/a/21400416/377875 Apparently, it's a problem with color space. Something like this works: ffmpeg -i "$1" -i "$2" \ -filter_complex "[1:0] setsar=sar=1,format=rgba [1sared]; [0:0]format=rgba [0rgbd]; ...


2

You can use ffmpeg with the compand audio filter (a port of sox effect filter of same name) to "compress or expand the audio's dynamic range", but admittedly this is one of the more complicated audio filters. Example from the documentation Make music with both quiet and loud passages suitable for listening to in a noisy environment (whatever that means): ...


2

That's way more than h.264 can handle. The maximum resolution for h.264 is 4096×2304 with Level 5.1 or 5.2. http://en.wikipedia.org/wiki/H.264#Levels There are lossless codecs who can theoretically handle this video resolution but it would make no sense to do this. There is no hardware capable of playing videos in this resolution at any acceptable frame ...


2

According to the framemd5 muxer documentation: This muxer computes and prints the MD5 hash for each audio and video packet. By default audio frames are converted to signed 16-bit raw audio and video frames to raw video before computing the hash. The output of the muxer consists of a line for each audio and video packet of the form: ...


2

You are re-encoding the video rather than cutting out a portion of the stream. Any re-encode is going to produce quality loss, particularly when you cut the data rate to less than 1/11th of the original data rate. If you want to cut out a portion of the video, you need to use a tool like VirtualDUB to actually extract a portion of the actual video stream ...


2

Your understanding of what an encoder does is incorrect. It doesn't make up images to fill in the time between I frames. It does somewhat the opposite: it takes a full series of complete images and decomposes them so that only the I frames and the differences between them remain. What you're asking for is, in animation terms, called tweening. The linked ...


2

If you copied your command there then your issue is probably -acodec:0 mp. That should be -acodec:0 mp3. You can just use -c:a mp3 to apply the encoding options to all audio tracks at once, no need to apply them for each individually. Other than that your mapping is correct and shouldn't be the issue. Edit: To conclude the discussion in the comments ...


2

Given your are using a VPS this is no suprise (guessing you only have a single core with 1-3GHz) and you won't be able to crunch the conversion down to a few minutes. You can try using -c:v libx264 -presets ultrafast but I'd guess it will still take you about 45-60 minutes to encode. Also remove the -crf option when using a preset. Be advised that the ...


2

Seeing that in the text of your question you have started discussing other utilities, i will assume that you are not interested in sticking with ffmpeg, but rather in getting the job done. In my experience with libav and MTS i have had no problems with the framerate, the files get remuxed perfectly. I have just attempted the following with one of my files: ...


2

No this is not possible. Looking at this theoretically disregarding the codec you can not take away information and call it lossless, thats already a terminology problem. Applying a new color space without transcoding is also not possible It's not so easy to say whether this is even possible with certain codecs other than h264, it really depends on how you ...


1

As AJ suggests, there may be ffmpeg commands to compress, but I suspect that in any case you'll need to separate the audio and video (demux), operate on the audio, and remux or re-encode. Ffmpeg, AviMux, and other tools can demux and remux most AVIs. If there are defined sections with different levels, you can manually intervene using something like (free) ...


1

You can use FFmpeg to adjust the levels in your video files. There is an answer on SU that explains how to do that: http://superuser.com/questions/323119/how-can-i-normalize-audio-using-ffmpeg


1

I believe the answer to your question is "yes". I'm not super familiar with FFMPEG, but the easiest way I can see to accomplish your goal is to first extract the last frame to an image, make a video of a few seconds and then run an encode that concatenates the main video and your newly created video in one pass.


1

I followed Henderson's advice and wrote a little script to resize the images: $ cat jpg2mp4.sh test -d "$1" || exit tmpdir=$(mktemp -d -p .) counter=0 find $1 -iname '*.jpg' | while read jpg do convert -resize 1440x1080 $jpg $tmpdir/IMG_$(printf "%04d" $counter).JPG counter=$((counter + 1)) done echo ffmpeg -i $tmpdir/IMG_%4d.JPG test.mp4 ...


1

The problem is that a sequence of images is not a video file. In order to convert it to a video format such as h.264, it has to load an entire group of pictures (probably somewhere around 15 of them) and then perform a whole bunch of calculations to determine how the images are related to each other. It then uses that information to determine what to ...



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