Hot answers tagged codec
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Some general info about the formats used:
YouTube uses 4 container formats and 3 diffrent codecs. It depends on the popularity of the video what codecs are used for your video (see below why). Generally, every of your uploaded video will be encoded in h.264 and will be muxed into an .flv and .mp4 container. Thats the standard and this will hapen for every ...
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The only ubiquitous one is mp3. AAC is great on Apple products, but only mp3 works on everything.
When storing voice audio you can go for a very low quality, and potentially use mono if you don't require stereo. This will give you very high compression - approaching that of speex.
From the Wikipedia comparison page
Bit Rate:
mp3 8 to 320 kbit/s
speex ...
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What you are describing is effectively what 2-pass VBR does for you. It makes a first path that calculates the level of change for each particular time in the video and then uses this information to make the best possible use of the available storage space.
It is, however, entirely possible to do the process manually by doing multiple encodings with ...
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There's a philosophical difference between delivery codecs (e.g. mpeg4, avchd), editing codecs (e.g. DNxHD, ProRes, Cineform), and capture codecs (e.g. r3d, DVCPROHD). While almost any codec can be used for each of these three stages, your workflow needs will help you decide which are best suited for each stage.
The question you seem to be asking, is ...
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Personally I always choose MP4 container and the H.264 codec as this is also the codec YouTube uses in the final video stream.
What key-frame rates and compression you need really depends on the footage and it's unfortunately close to impossible to give as a generic answer for this reason.
If you have a lot of movements you will need key-frames more often ...
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What format YT output their video depends on various factors. For most ordinary videos they use H264 encoded streams for video (AAC or MP3 for audio) in form of MP4 and FLV container files.
These are just containers holding the encoded video data - although the H264-encoded format is no guarantee with FLV-files (or in theory with MP4 files) as they can also ...
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You're on the right track with -crf and x264 (the H.264 encoder), and it should provide the "quality threshold" that you're looking for. CRF is recommended if you want a certain output quality and output file size is of less importance. Conversely, performing a two-pass encode with -b:v is recommend if you are targeting a specific output file size and ...
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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 ...
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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 ...
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The best quick, comprehensive, practical introduction to the film pipeline that I know of is the DV Rebel's Guide by Stu Maschwitz. It doesn't cover everything in depth, but it will give you enough terminology to know what else to search for. Film and video have very different workflows, but based on your question, it sounds like that may be part of what ...
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I'll start by pointing you to another answer I wrote before, roughly covering the different kinds of codecs.
(Nice edit on your question, by the way, removing the file size limitation helped figure out what you were after.)
My recommendation (again) will be to either use ProRes 422 or Cineform as your intermediate, probably via Magic Bullet Grinder or ...
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Codecs are algorithms, so as such they are completely independent of a programming language.
That said, there are plenty of open source codecs implemented in C that you can learn from. For example, take a look at the libavcodec library which has a large variety of codecs, some very complex, and some not so much.
I believe to make sense of the code you ...
2
Let me describe what the bottleneck in seeking is.
You didn't say what format are your videos encoded in, but I'm guessing you are using H.264 or maybe MPEG-2. Am I correct?
To maximize quality, these codecs have different compression formats, and each frame gets encoded differently. This is a brief summary of the compression types:
I-frames (I stands ...
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For a server, you definitely want ffmpeg. I would also strongly recommend compiling it yourself (those are Ubuntu instructions, but should work for Debian as well AFAIK) - the best AAC encoder available for ffmpeg (libfdk_aac) cannot be redistributed alongside x264 (because of the GPL), and the version of ffmpeg in the repositories is probably too old for ...
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neroAacEnc is also available for Linux. If you find that is works for you in OS X then you can use ffmpeg to pipe to this encoder and then mux with ffmpeg:
ffmpeg -i input -f wav - | neroAacEnc -ignorelength -if - -of audio.mp4
ffmpeg -i video.mp4 -i audio.mp4 -c copy -map 0 output.mkv
However, FFmpeg now also supports the external encoding library from ...
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Targa (TGA in the format options menu in AE) is a lossless codec that works with video (most people who know it know it from early days of image compression). It has better file compression ratios than Animation, but retains alpha support (32b/p). Its main advantage is that it's faster than animation.
PNG (as used in pictures on the internet) also supports ...
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DV has a something of a focus on simplicity, so it can be encoded with primitive microprocessors and decoded quickly in an NLE. In particular, it's intra-frame: a DV file is basically an array of still-image files.
That's useful for professional editing; it means however DV can't achieve nearly as high compression ratios as more complicated formats with P- ...
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For archiving VHS I suggest using MPEG2 720x576 as the best format in terms of quality/space.
DV is 12 GB per hour, but this is the best format for editing. H264 takes up much less space, but it is the delivery format, not for editing. MPEG2 is a compromise. In addition, you can burn them to DVD w/o reconverting.
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Ut Video is an editor friendly lossless video codec and is a good choice for in house production as an intermediary. It is fast, open source, actively developed, supports RGB(A)/ULRA (for your alpha channel requirement) and YUV colorspaces, and is available for Windows, OS X, and Linux. You can install it on Windows and it will show up in Adobe Media ...
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Video transcoding is very confusing and there is loads of different options.
If you dont want to use FFMpeg you could try VLC
Read more about transcoding with VLC here
Otherwise FFMpeg (or some kind of wrapper tool) is your best bet.
By omitting the -vb option you let FFMpeg decide bitrate. There is also a few Presets you can use for encoding to specific ...
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One way is to ask the people in the shop you intend to buy from.
Or (if you plan to buy online), narrow down to a list of potential cameras then ask again here with specific camera names.
Another idea is, if you have a compatible memory card, go to shop, ask to try the camera then shoot some video with your memory card in.
Then you can bring your memory ...
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I would go to VLC in the first instance. It's benefits include:
Great format support
Cross platform
Free
Here is a handy list of the formats supported; it indicates that it supports "AAC - MPEG-4 part3". This article on Wikipedia also gives a good list of alternative players that support either the encoding or decoding of MPEG-4 SLS.
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Put keyframe distance in the encoding options to KEY EVERY FRAME.
When you export in the export options you have keyframe distance, which is used to calculate "intermediate key points/key frames", and the default is 25/30 frames. The player calculates pixels and frames inbetween keyframes. Sometimes it gets lost in calculation because of lost bits or bytes. ...
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You want to use VirtualDub to convert your FRAPS files. Just drag the clip into the window, select video from the top menu -> compression. Change the codec to Avid AVI Codec 2.0d2 and then configure it to your desired resolution. BAM! The outputted files should work.
You can also try MediaCoder and XVid
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It also depends a lot on your target platform. High Profile will compress better than Main Profile, but not all devices can decode High Profile with large frame sizes. A few cannot decode High Profile at all.
I have had considerable success encoding motor racing in SD (852x480, actually) at 768kbps using High Profile. Even though you have a quarter the ...
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If you are going for a lot of motion, make sure you set a higher I frame rate. An I frame is a whole frame that you are going to need with quick motion.
Also, check out this link http://www.adobe.com/devnet/flash/apps/flv_bitrate_calculator.html for some basic settings. That shows you that 150kb/s is way to slow to keep a good picture. For SD material, ...
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I've never encountered this problem, so unfortunately I can't give you advice on how to fix it. However, next time, I would suggest that you convert all your footage to the same format before you begin editing. Prores 422 is a great editing codec.
Go to this website and download MPEG Streamclip. It's a free program that converts your footage to different ...
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