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8

tl;dr: Since Youtube reencodes all videos regardless of the upload format, it really isn't that important. Just export your video with a high bitrate to preserve quality. Also see my answer here regarding quality loss caused by Youtube. Long answer: Each reencoding of a video to a compressed format lowers the quality. Usually, that means you'll lose quality ...


5

YouTube will re-encode whatever you give it. VP9 is currently too slow to encode. So the best choice is to either: Give it the original footage, or if it is not accepted by YouTube or is too big to upload, then... Re-encode to H.264 ffmpeg ffmpeg will accept just about any input and will provide a great quality output. Development is very active, so it ...


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 ...


4

MP4 isn't an ideal format for intermediate saves. If you know you'll be re-opening the file, save it as losslessly as practicable, and use MP4 only for the final output. That said, depending on the encoder and settings you probably don't lose much if anything on subsequent saves. MP4 and similar codecs work by decimating the higher frequencies (details, ...


3

I would get as far away from EE as possible. Using the x264 tool, and mp4box, you can convert and segment out the files which are ready to be streamed to any dash compatible players. Especially since you mentioned using batch scripts, this is a great solution I think. This is a good guide: ...


3

The fourth stream apparently is a CEA-608 subtitle stream, which during the days of analog television signal transmission was caption data embedded within the video data. Apparently FFmpeg can extract it but can't mux it to a new container. As for stripping only the audio, MP4Box may be of help.


3

Rotate without re-encoding You can add rotation metadata: ffmpeg -i input.3gp -c copy -metadata:s:v rotate=90 output.3gp -c copy will enable stream copy mode, so it will just re-mux instead of re-encode. Player and device support for the rotate metadata may vary, so your player or device may not actually rotate the video. If that is the case you may ...


3

You can only estimate the bitrate as proportion of your crop. If you have 30,000 Kbps for 1920*1080 pixel, then for 1080*1080 pixel this would mean 16,875 Kbps. If there is more complexity inside the crop region than outside, I would even increase the target bitrate further. However, if your videos are not that long and not intended for streaming I wouldn't ...


3

Judge based on the quality rather than the bitrate value. Use CRF mode encoding and if the quality isn't what you can accept, decrease the CRF value. ffmpeg -i "%%a" -s 3840x2610 -c:v libx264 -crf 18 -acodec copy D:\%%~na.mp4


3

You can use ffmpeg, a free command-line tool, to do this: Without letterboxing, NTSC wide pixel-aspect ffmpeg -i input.mp4 -vf "scale=720x480,setdar=16/9" -r 30000/1001 -c:v libx264 -crf 20 -c:a aac -movflags +faststart output.mp4 With letterboxing, NTSC 4:3 pixel-aspect ffmpeg -i input.mp4 -vf "pad=1920:1440:0:180,scale=720x480,setdar=4/3" -r ...


3

Short answer is No. Longer answer is, it depends. If you're encoding a file, then generally the output is the duration of the input, unless there's speed change or trim filters or -ss, -to, -t options applied. For a live input, FFmpeg will stop the encode when it encounters EOF on the input, so unless you know that, you won't know the output duration. For ...


2

Maybe someone will chime in with an app suggestion that directly fulfills your need, but here's a temporary workaround - a bit convoluted, but should work. Create two folders A and B. Set folder A as the destination folder in the encoder. Apply a suffix to all the output files being generated, something innocuous like ENC e.g. Clip2015-09-25-23232-ENC.mov ...


2

Yes, MPEG-2 video is stored as YCbCr, but video editing programs (like Cinelerra) convert the samples to RGB for processing during editing. That range is 16-235. From Wikipedia on YCbCr Analog YPbPr from analog R'G'B' is derived as follows: To get a YUV output in the 16-235 range, the input RGB is also limited.


2

In strict mathematical terms, no. In terms of maintaining an acceptable image quality, yes. If you use CRF 18 and a preset like ultrafast now, you should be able to get a smaller acceptable file with preset veryslow later on.


2

You can't avoid the re-encode. They do this to be sure that every video they serve is in a standardized format, resolution and bitrate. It would be inefficient and risky to vet all diverse set of incoming files to check if they meet all their parameters, some of which are not easily available to set or tweak at the user's end.


2

Strictly speaking, fourcc is the codec ID used by Microsoft. It has been adapted for use with many other formats, thus making it seem like a standardized ID format, but it's not. ffmpeg, in particular, seems to only consider XDCAM standard MPEG2 for inclusion in MOV. From the source code: else if (track->enc->codec_id == AV_CODEC_ID_MPEG2VIDEO) ...


2

I not sure if I understood your question correctly, but CasparCG would be a common solution to overlay graphics (or anything else) to a video feed. http://www.casparcg.com Or, if you want to do this in software, take a look at the liquidsoap library: http://liquidsoap.fm/doc-svn/video.html


2

You need to convert the codec used to encode the video to something that the players you are trying to use support. MPlayer supports a wider range of codecs than many players. To allow you to view the video in other players you need to transcode the video using an application like ffmpeg. The command below will provide the conversion you need: ffmpeg -i ...


1

The first problem you have to solve is whether the flickering you see is part of your animation or part of the video encoder. If you have bad normals in your faces, you'll see a flicker. ProRes 422HQ produces a video file that's both low enough of a bitrate that most modern (post 2008) hardware can play without dropping frames, as well as high enough of a ...


1

My earlier answer still holds in general. Additional advice I can provide is to try higher CRF values and use the veryslow preset. ffmpeg -i input.mov -c:v libx264 -crf 23 -preset veryslow -c:a copy -c:d copy -map 0 compressed.mov You can also mimic a constrained quality mode by setting ffmpeg -i input.mov -c:v libx264 -crf 21 -preset veryslow -maxrate ...


1

If it's just a matter of which FOURCC to assign, and not the codec, then choose MP4V since it has broader compatibility, and the tag can always be changed later, using a tool like ffmpeg i.e. ffmpeg -i input.avi -c copy -map 0 -vtag DX50 tagged.avi


1

Leave them as they are. If storage space is limited you could recompress them, but given that the files coming from the DSLR are already compressed, to get an appreciable size reduction you would have to throw away a lot of quality. As you're planning to edit them in the future - meaning another transcoding - this would be a last resort. Buy more hard ...


1

It does not make sense to speak of the size of an encoded frame in an inter-coded video stream, which is typical of MPEG-X videos. I-frames are self-contained but P- and B- frames are predicted frames and the final decoded result uses data from various inputs. On the other hand, the size of a single Group of Pictures (GOP) may be a meaningful measure. The ...


1

The Apple video uses a profile with fewer reference frames and also carries a streaming hint track. The following ffmpeg command template should create a quick seeking MP4 file: ffmpeg -i input -c:v libx264 -profile:v baseline -x264opts keyint=3:min-keyint=2 -{other video encoding parameters} -{audio encoding parameters} -movflags +faststart+rtphint ...


1

Yes, TS is capable of doing what you are asking. Weather OBS is, is another question (that I do not know the answer to). mkv MAY be also to as well. But mp4 and mov can not do this.


1

You should upload the highest quality your tubes can afford. The current YouTube help text on uploads is misleading. It states: Your videos will process faster if you encode into a streamable file format. For more information, visit our Help Center. It contradicts what Colleen Henry, formerly of Google, now at Facebook said: Colleen Henry, Video ...


1

I've played around with turning a bunch of still photos into a h.264 slideshow, mostly to compare the compression efficiency of JPG vs. h.264. I got some useful replies about the technical implications of this from x264 devs on doom9. e.g. force x264 to not use B frames for this, because not-very-related images will need a lot of I macroblocks, and coding ...


1

Yes, some encoders allow changing parameters (like target quality or bitrate, or psychovisual tuning options (x264's aq and psy-rd options). x264, the stand-alone command-line frontend for the library, has a --zones parameter to give more bitrate to some parts of the video. So you could for example reduce the quality for the credits. The actual x264 ...


1

Unfortunately I couldn't find it in Adobe Encoder preferences - there is no such settings, and by default it loads 30fps sequence. You can change the default in Media Encoder by going to the Preferences/Media and then change "Indeterminate Media Timebase"


1

WMV is not lossless. As all distribution formats, it's highly compressed. An AVI file can of course be uncompressed, but on the Mac version of AE, AVI is only available as a Quicktime export component (ie, it appears in File > Export) which is really not a recommended path to export video files from After Effects. Same for Flip4Mac. So, yes, exporting a ...



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