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24

The -loop option is specific to the image file demuxer and gif muxer, so it can't be used for typical video files, but you can use the concat demuxer. Concat demuxer Make a text file. Contents of an example text file to repeat 4 times. $ cat list.txt file 'input.mp4' file 'input.mp4' file 'input.mp4' file 'input.mp4' Then run ffmpeg: ffmpeg -f concat ...


12

A really good program you can use is Handbrake. It's a very popular program among so called "pirates" because it's really good at getting a high quality even at tiny file sizes. And this is with good reason, because the main purpose of Handbrake is, indeed, to make the movies small with high quality. Personally I use it when I distribute my short movies on ...


7

IANAL, but as far as I understand it, if you're charging viewers for h.264 / MPEG-4 AVC content you do need to pay license fees. Even though x264 / ffmpeg are Free with a big F, they are just software libraries for encoding video streams into the H.264/MPEG-4 AVC format, which is covered by the MPEG patent. But the threshold for when fees are applicable is ...


5

No most video formats (nearly all) do not allow custom ICC color profiles to be embedded. (Improvemet/correction: MP4s can have color profiles tagged in the metadata of a video file.) most video on the consumer end is intended for the REC.709 color space. sRGB is similar and uses the same primaries. transcoding (including compressing) will almost always ...


5

What is your definition of huge and what is your definition of high quality? Size is directly related to compression and compression is directly inversely related to quality for the most part. Some amount of compression can be had for free using lossless compression or near free with more efficient pattern finding for lossy compression, but for the most ...


4

The key is to dial in the bitrate - you'll need about 800kbps video with 100kbps audio to hit 200MB. That's low for for SD resolution, but it might be good enough for you. Also look for software that has an option for 2-pass encoding. Try Expression Encoder, Adobe Media Encoder, or Sorenson Squeeze.


4

To force a keyframe at the 00:00:00.000 time code, you should try using the following flag: -force_key_frames 00:00:00.000


4

Both MKV and MP4 are container file formats. Container formats define how actual audio, video, subtitle and other data are structured. MKV is an open standard format, while MP4 comes from the ISO and is based on the QuickTime file format.


4

The .mpg and .mpeg extensions are typically associated with MPEG-1 and MPEG-2 files. The structure of these files is different than the .mp4 format used for H.264 video, part of the MPEG-4 family of formats. I suspect VLC and WMP can play the file because they must not be using the file extension to determine file type, they probably parse the file with all ...


4

I think the simplest way to this is to use MP4Box. ./MP4Box -add file1.mp4 -cat file2.mp4 -cat file3.mp4 output.mp4


4

Edit: I should probably remove some of the worrying conclusions about using x264 / ffmpeg that I now believe are unfounded. I put a section at the end to clear it up. For now I'm going to leave the whole mess here. Don't panic, x264 and ffh264 appear to be fine, legally, even for producing commercial videos at the standard royalty rates. Just to clear up ...


4

You can use AtomicParsley to parse the metadata of a MP4-file. For example AtomicParsley /path/to.mp4 -T 1 will print the whole atom tree.


4

Hope this explanation is what you're looking for: When you transcode to an encoding such as H.264 (MPEG-4 part 10) you necessarily also resample the video, that's part of H.264 compression technique. Nontheless, I doubt if this is the reason you experience a timing gap since the resampling doesn't necessarily influence the clock rate of the media. So, I ...


4

The Mainconcept or Sony codecs in Vegas are subpar for low-bitrate output such as needed for HTML5 use. Use ffmpeg to generate your HTML5 videos. Yes, mono audio is acceptable for HTML5 use, but once you use ffmpeg/x264 for generating those videos, the 6kB/s savings you get from switching to mono audio won't matter much if at all. Get the 32-bit static ...


3

Banding isn't uncommon in compressed video files, and can is exacerbated by the type and level of compression...there's also the bitrate of the original file and the final output. Lot's of points along the chain can cause banding. But I'd guess it's in your final output. What software are you using for rendering/conversion, and what are the render settings ...


3

As it was shot by its creators is kind of a nebulous concept, particularly when compression is involved. Color reproduction varies greatly from one device to another and without a calibrated display and a complete chain of color control going back to the source, you aren't going to get exact. Even then, chances are good that somewhere along the line the ...


3

Be aware that you are not changing anything. If I call you Bob, you are still Jac and even then you are probably posting under a different name. If you have software that naively trusts the filename instead of examining the actual binary headers of the file, this can work for you. If the actual format or encoding is wrong then no name change will fix that. ...


3

Yes, this simple conversion should work fine. Both files are technically mp4 files anyways. Only notable thing is that certain older Apple products, like older versions of appleTV for example, require it to be in m4v format so don't forget to switch it back if your switching between a Mac and a PC if you are using older mac products. By default, m4v files ...


3

MP4 has not really an official meaning. But it adds a lot to the MPEG-confusion: MPEG-4 part 14 container: takes an .mp4 file extension, therefore often just called MP4, if it contains audio, it can also have the .m4a extension, for video .m4v, and others (.m4p, .m4b, .m4r). the container format is a derivative of Apple QuickTime's container format (.mov). ...


3

Somewhat of an duplicate of: Can I manually change an .mp4 to .m4v by changing the extension in the Finder (mac) or explorer (win)? MP4 and M4V are essentially the exact same thing, M4V is usually used to indicate video only files but some sofware/companies are using it for standard MP4 files with video AND audio (lots of Apple software f.e.). It's just a ...


3

Sure - it seems ok. However, it is also a good idea to offer other types of video for browsers that do not support mp4 / h264. The usual best practice involves supplying mp4, webm and ogg as containers. This site is a good reference. A back of the napkin calculation: 1000 viewers / month @ 7.4 MB = 7.4 GB / Month. Which is probably within the acceptable ...


3

The solution was to turn off IE-11's "hardware acceleration" feature which (says here) "lets Internet Explorer move all graphics and text rendering from the CPU to the Graphics Processing Unit (GPU)". I disabled that under Tools -> Internet Options-> Advanced by selecting "Use software rendering instead of GPU rendering". It's pictured here Then, after ...


3

At least on FFmpeg 2.8.x (but oldie should works too) you can use lavfi as input format and complex filter graph using movie and setpts filters as a argument for -i option. Next command doing this work for you: ffmpeg -re -f lavfi -i "movie=filename=input.mp4:loop=0, setpts=N/(FRAME_RATE*TB)" output.mp4 Zero loop= arguments means infinity loop. Values ...


3

I encountered the same issue when I turned the sound off in the sequence. When I re-enabled audio export, even though I didn't want to or need to, it saved as an mp4 again.


3

There's no way to do this losslessly, other than setting a meta-data flag and depending on players to rotate the video. (This is what cell-phone cameras do). With avconv / ffmpeg, what you're doing is using your decoded -> transposed video as a source to encode with x264. See https://trac.ffmpeg.org/wiki/Encode/H.264 for how to do this. IDK where you ...


3

One big loss in converting VHS to DVD arises from going through the composite domain. Both VHS and MPEG2 use a separated chroma paradigm -- on the VHS tape are two signals, essentially luma and bandwidth-limited chroma. MPEG2 (the standard for DVD) also uses separate luma and chroma. But the standard output from a VHS player combines the signals in a way ...


3

Yes, it seems to be a problem of generated timecode. See https://trac.videolan.org/vlc/ticket/12713#no1 Switch to ffmpeg (with a GUI like Avanti) to avoid this issue. My answer to an earlier webm question may guide you on settings.


3

All that matters is if the MP4 looks good to you. Of course, you may be able to compress more. There is no set bitrate to use. More complex or rapidly changing visuals require greater bitrate. Most converters use x264 to generate the converted video stream, and x264 offers a CRF mode which adjusts the bitrate based on the visual content complexity. If your ...


2

ffmpeg will do it for you - http://stackoverflow.com/questions/5887311/ffmpeg-1-image-1-audio-file-1-video If you want to provide good seeking ability, you will need to provide key frames at certain intervals in the encoding, which will increase the size of the video. The codec will encode the whole frame at each of the keyframes but greatly compress the ...


2

Unfortunately you are not going to be able to accomplish your goal. Two major factors impact this. First, color processing on different systems is going to differ. This will result in slight differences in the colors that are displayed because many video players apply "enhancements" to video and what you actually see when viewing the video in a browser is ...



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