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2013/1/1 Michael Mol <mikemol@×××××.com> |
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|
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> On Tue, Jan 1, 2013 at 5:19 PM, Nuno J. Silva <nunojsilva@×××××××.pt> |
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> wrote: |
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> > On 2013-01-01, Stroller wrote: |
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> > |
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> >> On 30 December 2012, at 11:39, Nuno J. Silva wrote: |
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> >>> ... |
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> >>> The AVI container has been used by windows for a long time, so I'd say |
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> >>> chances are that it will work on more systems, but I can't say for |
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> sure. |
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> >> |
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> >> But h264 in an AVI is invalid. |
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> >> |
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> >> AVI is dated and just plain nasty. |
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> >> |
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> >> You should use something else (like h264 in an MP4) if you possibly can. |
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> > |
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> > AVI is old, AVI has issues. AVI is not compatible with some |
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> > codecs. *But* AVI has been around for long enough to be supported by |
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> > many versions of Windows and Office, and what we're looking for here is |
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> > whatever offers the broadest support. I don't even think Windows (at |
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> > least up to 7) has a builtin h264 decoder. At least I remember having to |
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> > install codecs in Vista and 7 machines in order to view h264 Youtube |
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> > videos. |
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> |
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> Did a bit of googling. Windows 7 includes h264 support. |
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> |
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> In any case, there's something *critically* important missing in most |
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> of this discussion about AVI vs something else. |
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> |
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> Just because Windows supports AVI doesn't mean that Windows includes |
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> all possible codecs you might stuff in an AVI. There's h264, there's |
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> MPEG, MPEG2, Theora, RLE Windows Media and hundreds of codecs I've |
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> forgotten. And that's just video. For audio, there's more variation |
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> than there is for WAV[1]. In addition to anything WAVE files might |
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> contain, you might find just about anything. There's FLAC, AAC, Speex, |
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> MP2a, MP3, Vorbis and thousands more. |
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> |
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> AVI is just a container. Nothing more. Containers are like ZIP files |
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> or tar files, but instead of containing a filesystem, they contain a |
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> variable number of audio and video streams in such a way that the |
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> audio and video data for a moment in time are close together and |
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> easily accessible. The meat is in the audio and video streams, the |
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> format of which we call codecs. |
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> |
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> The big question is what *codecs* are available on the target systems. |
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> |
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> If you're looking for the absolute widest degree of support, you're |
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> looking at DIB encoding for video with uLaw PCM for audio. But that's |
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> going to be a *huge* file, because there's no compression at all! |
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> |
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> The best compression that's going to be available on the widest |
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> variety of systems is probably going to be MPEG2 video with MPEG2 |
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> layer 3 audio. |
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> |
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> The best compression that might be available, period, would be h.264, |
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> combined with MP4 audio, in an MP4 container. Almost as good results |
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> can be had with h.264 video, MP4 audio in an AVI container.[2] |
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> |
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> So, Francisco, what version of Windows will your slideshow be played on? |
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> |
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> [1] Yeah, WAVE files aren't exactly simple, either. They can contain |
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> different PCM encodings. There's aLaw, uLaw, float... |
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> [2] For full effectiveness, h.264 requires features that the AVI |
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> container doesn't have. |
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> |
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> -- |
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> :wq |
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> |
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> |
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Wow, what a class! Thank you a lot, that explained much of my doubts. I had |
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no problems with audio, I use several programs and several codecs for |
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messing around with different audio file formats. But video was still a |
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mystery to me. |
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|
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As a matter of fact, I am not sure on what windows version this |
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presentation will be played, it is a training presentation, so I suppose we |
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can only expect at least XP. |
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|
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I will bring a free MS office player, so that part should not be a problem. |
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And also a "K-Lite" or any other codecs package installer. |
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|
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Thanks |
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-- |
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Francisco |
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"If you have an apple and I have an apple and we exchange apples then you |
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and I will still each have one apple. But if you have an idea and I have |
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one idea and we exchange these ideas, then each of us will have two ideas." |
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- George Bernard Shaw |