7

Look at ffmpeg. It will run on just about anything and should do what you want, although it might depend on what your source actually is Something like this should work : ffmpeg -i sourcefile.avi -f image2 'img-%03d.jpeg' (see the image2 section for full reference)


7

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 ...


7

BTW, this question might be better on stackoverflow, or maybe unix.stackexchange, or maybe serverfault. This site is I think less focused on questions that don't involve decisions based on creative merit or at least perceptual video / audio quality. However, I'm all about the tech details, so I'll answer. FFmpeg uses multi-threading by default, so you ...


6

Note: This is for recent FFmpeg, not FFmbc, which doesn't use the same option syntax (yet) You need to use the -profile:v option, which has been introduced in FFmpeg 0.9 (afaik) and is now standard in 1.0. ffmpeg -i input.mp4 -c:v libx264 -preset fast -profile:v baseline out.mov Why? -profile was used (and prioritized) for AAC encoding. It's simply ...


5

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


5

The CRF scales for x264 and x265 do not correspond. x265 CRF 28 is supposed to be equivalent to x264 CRF 23. But x265 is not yet as mature in its development as x264, so take that CRF equivalence with a pinch of salt. That said, you can try to establish your own calibration between the current versions of the encoding libraries in your ffmpeg by running ...


4

This isn't a phenomenon, this is compression. It is simply how it works. Compression works by taking an input, runs it through some algorithms and then gets an output that matches up either exactly (lossless) or approximately (lossy) with the original input. It is not stored like normal video data as a set of pixels, but rather some form of data that ...


4

To understand this you need to understand how codecs actually work. A plain uncompressed video frame e.g. a single picture is pretty large. I'm talking about a bitmap, not a lossless encoded video, no encoding at all, just plain pixel information. Here simple example of a Full HD frame for some perspective: We have a resolution of 1920x1080 that equals to ...


4

For a good GUI based on libavcodec (which a ffmpeg library), take a look at handbrake. Might be a bit too detailed for a very "simple" user, but with some effort it's manegable. It also supports saving of presets, so you can set it up for easy use.


4

-profile baseline seems to work for me, using libx264. I use the libx264 presets - for example "slow" gives me the options listed below. there's fast, slow, veryslow and placebo (might be more, can't remember). stib$ ffmbc -i test.mov -vcodec libx264 -preset slow -profile baseline -acodec libfaac -ab 96k -crf 19 test.mp4 ... [libx264 @ 0x101858c00] profile ...


4

libtheora is single threaded. There is a multithreaded experimental build, but is not maintained. I would suggest running it in parallel with the other encodes. Also if possible use libfdk-aac over libfaac. Much higher audio fidelity at the same bitrate.


4

Although @stib's advice is sound, I disagree with "to get an appreciable size reduction you would have to throw away a lot of quality". Cameras have to compress on-the-fly, so they use constrained baseline mode, which is to say, they skip most of the tricks that H.264 codec uses to efficiently compress videos. If space isn't a pressing concern, keep them as-...


4

A direct option to resume encoding is not available. And as for manually restarting encoding, that's also not possible. Two reasons: 1) when transcoding to a typical container like MP4, the index is written after encoding is completed. There will be no such index in a partial file if the process died unexpectedly, and so the existing file cannot be parsed. ...


4

I've worked through a similar project over the last 6 months, and performed more tests than I can keep track of now. So this is a little fresh for me. With your questions: 4K camera -> capture card -> Linux PC (compression) -> RTSP This will work well Are blackmagic ursa mini 4K and decklink card able to do the first 2 stages respectively? Yes ...


3

A lot of these answers seem somewhat misleading unfortunately. Forget about getting a capture card. Practically every one has AGC. AGC is very similar to macrovision, except it's superimposed onto any video source. It's impossible to disable unless you use Linux and know your way around hacking drivers. Some cards on Windows have third party tools to ...


3

...FFMPEG worked, it was a steep learning curve in terms of getting it to work in my environment and, took me a few days to learn how to code in Bash Scripts Shell based, but in the end very happy with the results and it's integration with both Macs and my Unix server.


3

You didn't mention whether you're using a Mac or Windows, but... You could use a tool like MPEG Streamclip to change the format of the video, or strip off the audio. Works on both Mac or Windows.


3

1) If you're not going to deinterlace it then stick to the source's field order. 2) I wouldn't bother with the two pass encoding (if indeed it even does anything) - dnxhd will only encode at certain specific fixed bit rates anyway so you're actually pretty constrained for options. 3) You'll see some softening, but it's unavoidable. ffmbc's filtering is ok ...


3

Rather than using constant bitrate, have a go using constant quality (AKA constant rate factor, or crf). So instead of -b:v 2000 use -crf 23 (adjust the number to change the quality, higher is smaller / lower quality and lower is larger / better quality). Constant quality usually gives you more bang for your bits, as it skimps on bitrate where it's not ...


3

A common method is split-and-stitch where the file is cut into pieces and sent to multiple servers for transcode. That way you can transcode a file of any length in a fixed amount of time. Telestreams Episode Engine can do this, but I'm sure Google uses something custom coded.


3

There are two main features in NVIDIA NVENC encoding: Video memory if you need to transcode many streams. NVENC SIP - than better this SIP than better encoding performance is. It depends on GPU. You can find the best explanation related GPU and NVENC SIP generation on Wikipedia website. Maxwell Gen 2 is the best at the moment(for 2016). According to the ...


3

If the only difference is bitrate, then any container which accepts variable bitrate streams, will fulfill your requirement e.g. MP4, MKV..etc Step 1 is to encode your segments, ideally using the same encoder, to different bitrates with all other parameters being the same e.g. via ffmpeg, ffmpeg -ss 0 -t 5 -i input.mp4 -b:v 1000k seg1.mp4 ffmpeg -ss 5 -t ...


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 ...


3

It's an issue with new video drivers. Everything is fine with video driver 361.28 and lower. I already sent this issue to NVIDIA Support with Reference Number 161118-000164 UPDATE: This issue has been resolved from the 375.39 driver. It allows keep interlacing on Pascal 10x video cards.


2

Fixed by updating FFMpeg to newer version


2

You could create a droplet in compressor. Unfortunately, your options for destination folder are limited by this method to either source, desktop, cluster storage, or your movie folder. Since you don't want your watch folder endlessly copying movies, "source" is a bad choice, and you probably don't have cluster storage, so as long as you're ok with your ...


2

I struggled with a similar issue on Ubuntu 12.04.3 LTS. I fixed the problem using the static ffmpeg build which is available from http://johnvansickle.com/ffmpeg/


2

Why convert to OGV when your final upload is going to be to youtube, I may be wrong but you can convert to x264 video codec with AAC Audio even on linux and upload that to youtube considering that is what they prefer to be uploaded anyway. Have you tried making an h264 and uploading to youtube instead of the OGV file and seeing if that was the issue. ...


2

I do this all the time for local user groups and I'm yet to find a "plug and play/set and forget" solution. To do the recordings at a professional quality, you need some sort of skill and training, otherwise it will look amateur. If all you want to record is the person talking, and not what's on their screen, it's relatively easy: buy a wireless lapel mic (...


2

Generally, I would expect that just about any solution will work pretty well now. The capabilities of even cheap modern hardware so far outpace the capability of laserdisc that you aren't likely to lose much. Certainly a professional quality capture system similar to the ones Matrox sells would do a superb job, but I'd hazard that even a cheap $30 USB to ...


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