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  #1  
Old 10-18-2011, 10:50 AM
Rhythmdvl Rhythmdvl is offline
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Why does video conversion take so long? Any tweaks?

Converting from one format to another (my experience is primarily converting to FLV format with Adobe Media Encoder CS4) takes a relatively gargantuan amount of time. I occasionally see a trivia note on IMDB that such-and-such a scene took x-processing years to do. What’s going on under the hood? What makes it so processor and/or memory intensive?

As for tweaks, is there anything I can do/set on a PC to optimize the process? If it makes a difference, I have an i7 920, 6GB RAM, and two ATI HD 5700s (Crossfire). More RAM? Some setting in the ATI control panel?
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  #2  
Old 10-18-2011, 10:58 AM
Musicat Musicat is offline
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It's a shitload of data. Converting from one format to another usually involves expanding a compressed file to individual frames, re-encoding and re-compressing.

As far as tweaks, there are many, but they are probably specific to the files, hardware and software you are using, so I doubt if I could help you. In general, disk writes are a bottleneck, so the more you can minimize those, the better. Maybe a RAM disk?
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  #3  
Old 10-18-2011, 11:20 AM
JoelUpchurch JoelUpchurch is offline
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If you find a magic formula tell me. I can peg a quad core and it is still takes over an hour to convert an hour of video for most formats.
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  #4  
Old 10-18-2011, 11:23 AM
Rhythmdvl Rhythmdvl is offline
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Is there a good non-specialist overview of the process out there? Something to satiate the need-to-know-how-something-works area of the brain without expecting me to roll up my sleeves and become fluent.

How do players differ from encoders (is that the right term)? If players can expand in real-time (or appear to expand in real-time), why does this factor into the overall time to change format? And if recorders (e.g. cameras) can encode in real-time (or appear to), how do these add up to such a dramatic effect?

Note that I'm not doubting the explanation--I'm asking these to expose more and more of my ignorance on the subject.

...

In terms of speeding things up, my boot and application drive is an SSD. I don't like to put data on it (256GB isn't exactly roomy), but if it will speed things up I can certainly allocate some temporary space. Or would a RAM disk be a better idea.

Oh, and RAM disk? I don't think I've used a RAM disk since I was on a DOS machine. Funky.
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  #5  
Old 10-18-2011, 11:44 AM
beowulff beowulff is offline
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One big reason encoding takes so long is so that decoding can occur in realtime. All the hard work is done at the encoding stage, when there is plenty of time, so the decoding engine doesn't have to be very powerful or very fast. For example, one technique used to compress video substantially is to use motion estimation. This requires the encoder to look at sequential frames and determine which areas are moving and which are static, and then encode the motion changes from the key frame. Clearly, this is a lot more processor-intensive than the decoding, which just needs to move the pixels around.

Generally, encoding is processor-bound, not I/O bound, so doing everything on a RAM disk isn't going to help very much. A faster processor with more cache will help, as will more cores (if your compressor is well threaded).

Last edited by beowulff; 10-18-2011 at 11:44 AM..
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  #6  
Old 10-18-2011, 11:58 AM
Heracles Heracles is offline
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Quote:
Originally Posted by Rhythmdvl View Post
I occasionally see a trivia note on IMDB that such-and-such a scene took x-processing years to do. What’s going on under the hood? What makes it so processor and/or memory intensive?
In this case, it's not video conversion. The CPU times mentioned on IMDB and such are rendering times. This is when a movie such as Up or Toy Story is drawn, frame by frame, by computers. For each frame, the computer must determine how the various objects are placed, how each hair on the dog's back is reacting based on the "wind" and on its recent movements, and then each pixel has to be given the correct colour and intensity it should have for a semi-reflective, golden object that is lit thusly and is sitting next to that checkered red-and-white ball. Repeat 150000-200000 times for a 2-hour movie. And of course the whole process is done repeatedly until it "looks" right. At least once in HD.

Of course, they spread the work among banks of computers, so the "years" are reduced to weeks or days.
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  #7  
Old 10-18-2011, 12:17 PM
muldoonthief muldoonthief is offline
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Quote:
Originally Posted by Rhythmdvl View Post
How do players differ from encoders (is that the right term)? If players can expand in real-time (or appear to expand in real-time), why does this factor into the overall time to change format? And if recorders (e.g. cameras) can encode in real-time (or appear to), how do these add up to such a dramatic effect?

Note that I'm not doubting the explanation--I'm asking these to expose more and more of my ignorance on the subject.

...
Dedicated devices, like camcorders, have an onboard chip that does nothing but encode to one or two specific formats. I know in the past you could buy encoder cards for PCs that did the same, but a CPU is general purpose, so cannot necessarily decode/re-encode in real time.
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  #8  
Old 10-18-2011, 12:19 PM
Rhythmdvl Rhythmdvl is offline
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Is that an absurdly suped-up (souped-up?) version of what my system does with games? In the games it goes quickly but it's only accounting for a comparatively limited number of variables.

If so, is there any comparison of a modern system (say the one in my first reply) to hardware used to render CGI effects in the 80s or 90s? In, say, fifteen more years of advancing technology, any chance that Crysis XII will look as clean as Toy Story? Or is the scale of distributed computing Pixar uses so vast that a single desktop won't reach such power for the foreseeable future?

ETA:
Quote:
Originally Posted by muldoonthief View Post
Dedicated devices, like camcorders, have an onboard chip that does nothing but encode to one or two specific formats. I know in the past you could buy encoder cards for PCs that did the same, but a CPU is general purpose, so cannot necessarily decode/re-encode in real time.
Is that the difference between desktop video cards and professional video cards?

Last edited by Rhythmdvl; 10-18-2011 at 12:21 PM..
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  #9  
Old 10-18-2011, 02:06 PM
groman groman is offline
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Originally Posted by Rhythmdvl View Post
ETA:Is that the difference between desktop video cards and professional video cards?
Not really. The professional graphics cards have just more generic processing power available that is only slightly more adapted to non-gaming usage. For speeding up video encoding you need a dedicated encoder card, such as:
http://www.matrox.com/video/en/products/mac/compresshd/
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  #10  
Old 10-18-2011, 02:41 PM
Musicat Musicat is offline
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Originally Posted by Rhythmdvl View Post
In terms of speeding things up, my boot and application drive is an SSD. I don't like to put data on it (256GB isn't exactly roomy), but if it will speed things up I can certainly allocate some temporary space. Or would a RAM disk be a better idea.

Oh, and RAM disk? I don't think I've used a RAM disk since I was on a DOS machine. Funky.
RAM disk = Solid State Disk. Same-same.

If we didn't have compression, processing would probably go faster, but the amount of data that would have to be read/written would be much more. There is a tradeoff here.

The encoding process takes raw, frame-by-frame, discrete data, one-pixel-at-a-time data, and, using very sophisticated algorithms, decides how it can be best compressed. Example: if only a tiny portion of a frame is different from the following one, only the data that is different needs to be saved; the data that is the same can be repeated. This provides an enormous amount of compression for very little loss as long as you have talking heads; not so much for sporting events.
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  #11  
Old 10-18-2011, 04:39 PM
psychonaut psychonaut is offline
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Originally Posted by muldoonthief View Post
Dedicated devices, like camcorders, have an onboard chip that does nothing but encode to one or two specific formats.
More importantly, the formats encoded by a camera are usually relatively simple ones like MJPEG. These formats aren't computationally intensive, but result in much larger file sizes. Your camera would be lucky to get a 1:20 compression ratio over the raw video, whereas a "proper" video format such as Theora or MPEG[124] can do 1:50 or better.
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  #12  
Old 10-18-2011, 04:57 PM
Chronos Chronos is offline
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Right, there's a trade-off between time taken to encode, time taken to decode, and file size. Generally, you want the decoding to be fast enough that most devices can display it in real time, so you have a hard limit there. Given that hard limit, you want the file sizes to be as small as possible, so people don't get bored waiting for them to download (and ideally, real-time over a realistic internet connection). So that's another thing you're optimizing. The only place left to do the tradeoffs is in the time taken to encode it more cleverly, and since that only has to be done once, as opposed to millions of times for the downloading and decoding, it's acceptable to spend a really long time on that step.
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  #13  
Old 10-18-2011, 06:45 PM
chorpler chorpler is online now
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Originally Posted by Musicat View Post
RAM disk = Solid State Disk. Same-same.
In my experience the term "RAM disk" means a virtual disk created by using part of the system RAM (or main memory, or whatever you want to call it) as a storage disk. It's much faster to write to RAM than it is to write to a physical hard drive, so for something where you're writing a lot of data, a RAM disk would be handy. And some systems now have enough RAM (this computer has 24GB and the servers next to me have a couple hundred gigs total) to give you enough room to do something large like video editing.

A solid-state disk is completely different, being basically just another hard disk attached to the system, but which uses flash RAM instead of spinning magnetic platters. Much faster to read from than a magnetic hard drive with its moving parts, but writing is much slower than reading, and the total number of write cycles is limited.
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  #14  
Old 10-18-2011, 07:01 PM
Derleth Derleth is offline
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Originally Posted by Musicat View Post
RAM disk = Solid State Disk. Same-same.
Of course not. Nobody uses the terms like that.

A RAM disk is a virtual disk made out of your dynamic RAM. All of the data on it goes away when your machine is powered down, if you don't manually destroy it first.

A solid-state disk is made out of non-volatile RAM, commonly Flash at this point. The data persists until and unless you either manually erase it or the chips fail.
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  #15  
Old 10-18-2011, 07:08 PM
Derleth Derleth is offline
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This is likely the single best video about how video encoding actually works for non-technical people. (Well, I say non-technical, but it has some real meat to it. I find it a good balance but some people might need to pause it every so often to digest the concepts.) It doesn't touch on conversion directly, but it does go into how encoding and decoding work.

VLC will play it if you don't already have a good video player installed. Or just grab VLC because it is, in fact, a good and free video player.

Last edited by Derleth; 10-18-2011 at 07:09 PM..
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  #16  
Old 10-18-2011, 07:11 PM
Keeve Keeve is offline
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I would imagine that another part of the complexity concerns the humongous number of pixels they're working with. YouTube stuff, I imagine, is somewhere between 600*400 pixels and 1280*800 pixels. If Hollywood tried that on a movie theater screen it would look horrendous. Anyone know how many pixels they typically work in?
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  #17  
Old 10-18-2011, 07:18 PM
beowulff beowulff is offline
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Originally Posted by Keeve View Post
I would imagine that another part of the complexity concerns the humongous number of pixels they're working with. YouTube stuff, I imagine, is somewhere between 600*400 pixels and 1280*800 pixels. If Hollywood tried that on a movie theater screen it would look horrendous. Anyone know how many pixels they typically work in?
Digital movies are in 2K or 4K format - 2048 x 1080 or 4096 x 2160
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  #18  
Old 10-18-2011, 07:28 PM
Musicat Musicat is offline
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As far as a RAM disk vs. SSD, all I'm saying is writing to some kind of non-moving memory is faster than writing to a moving platter. I'm aware of the differences, but as beowulff pointed out, video processing is more CPU-bound than I/O -bound. Still, when I am processing video, I see an awful lot of disk I/Os that I sure would like to reduce.
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Old 10-18-2011, 07:39 PM
chorpler chorpler is online now
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As far as a RAM disk vs. SSD, all I'm saying is writing to some kind of non-moving memory is faster than writing to a moving platter.
Aw, come on, a rolleyes?

In any case, I've never gotten write speed on a SSD to be as high as my hard drive. But I generally buy the cheapest SSDs I can find, which may affect things. Also, the real performance hit comes when copying many small files. Presumably a big video-editing write would not suffer from this problem (although I guess it depends on the specifics of how it writes).

A real RAM disk would be great for saving a video conversion's output, with the small problem of losing the results if/when the computer shuts off.

Last edited by chorpler; 10-18-2011 at 07:39 PM..
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  #20  
Old 10-18-2011, 07:45 PM
Musicat Musicat is offline
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In any case, I've never gotten write speed on a SSD to be as high as my hard drive. But I generally buy the cheapest SSDs I can find, which may affect things.
I haven't run any speed tests recently, but that's surprising. However, I think flash is slower to write to than RAM. And you could be witnessing the driver software's flaws. ETA: Or maybe the hard drive has more buffering and masks the actual write time?

I used to write low-level (assembly) software, using RAM to simulate a hard drive, many moons ago, and there is an art to efficient code. Poor code can overwhelm any speeds inherent in the system.

Last edited by Musicat; 10-18-2011 at 07:46 PM..
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  #21  
Old 10-18-2011, 07:47 PM
Dr. Strangelove Dr. Strangelove is online now
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Originally Posted by Keeve View Post
I would imagine that another part of the complexity concerns the humongous number of pixels they're working with. YouTube stuff, I imagine, is somewhere between 600*400 pixels and 1280*800 pixels. If Hollywood tried that on a movie theater screen it would look horrendous. Anyone know how many pixels they typically work in?
YouTube supports 4k video. Not very common, of course, since essentially no display devices support that res.
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  #22  
Old 10-18-2011, 08:09 PM
Musicat Musicat is offline
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To partially answer Keeve's question, I've always heard that 35mm film was equivalent to 2400 x 3600 pixels (=2400DPI), so that kind of digital resolution would approximate traditional, stock movie film. Once the gold standard that digital wanted to emulate, digital should be able to surpass film if the cost can be contained, and it can only get cheaper.
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  #23  
Old 10-19-2011, 01:16 AM
psychonaut psychonaut is offline
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And even at those resolutions, the image can still look horrendous. Line art and text particularly can come across as jagged; this is particularly noticeable with rolling credits and with some cartoons. Film may have a similar effective resolution, but because it's analog, pixelization isn't an issue.
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  #24  
Old 10-19-2011, 01:22 AM
psychonaut psychonaut is offline
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A real RAM disk would be great for saving a video conversion's output, with the small problem of losing the results if/when the computer shuts off.
The way modern operating systems handle input/output, it's already similar to a RAM disk. When you write something to disk, the OS actually writes it to a memory cache, and only flushes this cache to the physical media after the cache is full, or after a certain amount of time, or when the system isn't otherwise busy. This is why, with removable media such as USB hard drives, you need to tell the operating system you want to "unmount" or "safely remove" the hardware before disconnecting it; the OS needs to flush the cache and actually write the data.
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  #25  
Old 10-19-2011, 03:14 AM
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Originally Posted by Rhythmdvl View Post
In terms of speeding things up, my boot and application drive is an SSD. I don't like to put data on it (256GB isn't exactly roomy), but if it will speed things up I can certainly allocate some temporary space. Or would a RAM disk be a better idea.
I don't know why but that quote struck me as really funny. Funny in the fact that I am recalling my first computer with its huge 250mb hard drive. I remember purchasing my first 1gb hard drive. I don't remember the price right now, but I do remember the uneasy feeling in my stomach as I cut the check. Then again I distinctly remember paying $160 for 4mb of ram in the early '90s.
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  #26  
Old 10-19-2011, 04:24 AM
si_blakely si_blakely is offline
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What Rhythmdvl is doing is commonly called transcoding - converting one compressed video/audio file format to another. And (as noted) this is a slow process, usually involving multiple passes.

Generally, the original file is fully decompressed to raw, uncompressed video/audio. This process can proceed at faster than realtime, especially if the decompressor can use built-in hardware (i.e CPU or GPU functionality) to accelerate the process. An initial pass over the file may be required to identify key frames (where the image changes substantially so that motion compression cannot be used), and then the file is compressed. Depending on the compression being used, this may also be accelerated by hardware (ie compression cards or GPU). This process is also repeated for audio, and the output wrapped up in a container file. Multithreading on multi-core processors will also increase the speed.

For Rhythmdvl with ATI cards, ATI Avivo may be a GPU-accelerated possibility, but it looks like FLV may not be supported. The other options include the opensource products MPlayer/Mencoder or ffmpeg which can use hardware acceleration if you find the correct compiled versions. This option may not be useful on Windows, however.

Si
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  #27  
Old 10-19-2011, 04:50 AM
si_blakely si_blakely is offline
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Originally Posted by Rhythmdvl View Post
If so, is there any comparison of a modern system (say the one in my first reply) to hardware used to render CGI effects in the 80s or 90s? In, say, fifteen more years of advancing technology, any chance that Crysis XII will look as clean as Toy Story? Or is the scale of distributed computing Pixar uses so vast that a single desktop won't reach such power for the foreseeable future?
The major difference between Movie CGI and Gaming is raytracing. This handles multiple lighting, reflections, shadows, textures and caustics in a realistic manner, but is massively intensive computationally. While there has been work on realtime raytracing (I know someone who has worked on this on a PS3), the resolution and framerates are not yet sufficient. This will be the future of games, but the current model (polygon mapping with textures and light maps) will continue for many years.

Another point, while movies may be printed (or shown directly) as 2K or 4K, when rendered, they are almost certainly antialiased by supersampling (rendering at 2x or 4x the resolution and averaging to the intended resolution). This massively increases the compute requirements.

Si
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  #28  
Old 10-19-2011, 06:26 AM
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@ Rhythmdvl, if you have a lot of internet bandwidth, you might consider uploading your video to the cloud to transcode instead. Pay a few bucks and put an entire server farm to work instead of just using your desktop.

There are several dedicated services that do this (sorry, I didn't like any of the ones I tried, so Google around and find some yourself), or you can set up your own cluster on Amazon EC2 for (likely) the best performance.

Quote:
Originally Posted by Musicat View Post
As far as a RAM disk vs. SSD, all I'm saying is writing to some kind of non-moving memory is faster than writing to a moving platter. I'm aware of the differences, but as beowulff pointed out, video processing is more CPU-bound than I/O -bound. Still, when I am processing video, I see an awful lot of disk I/Os that I sure would like to reduce.
Did that really warrant a rolleyes? They're different, and as you yourself mentioned, RAM disks are typically faster than SSDs. In a thread about speed, that's somewhat important... not to mention the whole volatility thing. Conflating the two just isn't right.
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  #29  
Old 10-19-2011, 06:32 AM
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Also, maybe this is obvious, but videos you upload to YouTube get converted by them automatically, for free. Similar effect to cloud transcoding.
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  #30  
Old 10-19-2011, 07:10 AM
psychonaut psychonaut is offline
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Also, maybe this is obvious, but videos you upload to YouTube get converted by them automatically, for free. Similar effect to cloud transcoding.
They get converted to a proprietary codec in a proprietary container format which isn't convenient to use offline and isn't supported by most consumer electronics. Besides, in many cases it will take longer to upload the video to YouTube and wait for it to do the transcoding than for you to just do the transcoding yourself; doing it locally also gives you control over the resolution, bit rate, etc.
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Old 10-19-2011, 07:51 AM
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They get converted to a proprietary codec in a proprietary container format which isn't convenient to use offline and isn't supported by most consumer electronics. Besides, in many cases it will take longer to upload the video to YouTube and wait for it to do the transcoding than for you to just do the transcoding yourself; doing it locally also gives you control over the resolution, bit rate, etc.
Well, the OP said his/her most common usage scenario was transcoding to FLV, so I just assumed the video was going online eventually. If that is indeed the case, YouTube is often the best way to do it.

Proprietary or not, YouTube videos can be viewed on pretty much every major PC and mobile operating system. Its videos likely have the best market support, even compared to things like MPEG/H264/MOV whose per-device support (or lack thereof) is dependent on finicky encoding settings.

If you upload a video at its highest resolution, YouTube makes all the lower resolutions (240p/320p/480p, etc.) automatically available without any extra encoding work on your part.

And YouTube is quite reliable, fast, and backed by one of the world's biggest companies.

So if the video's going online anyway, YouTube is worth considering. If not, you're right, YouTube wouldn't be the best choice.

Last edited by Reply; 10-19-2011 at 07:52 AM..
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  #32  
Old 10-19-2011, 08:02 AM
Mahaloth Mahaloth is online now
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What is the best freeware program you guys know for video conversion? What is the best non-freeware one? I'm curious.

I tend to find that I lose resolution in video conversion, even if I tell the program to maintain the highest resolution.
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Old 10-19-2011, 08:20 AM
si_blakely si_blakely is offline
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What is the best freeware program you guys know for video conversion? What is the best non-freeware one? I'm curious.
I've used SUPER, which is a GUI front end to mencoder/ffmpeg. You can use mencoder directly, but be prepared to spend some time figuring out the command line options.

Si
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  #34  
Old 10-19-2011, 08:38 AM
JoelUpchurch JoelUpchurch is offline
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They get converted to a proprietary codec in a proprietary container format which isn't convenient to use offline and isn't supported by most consumer electronics. Besides, in many cases it will take longer to upload the video to YouTube and wait for it to do the transcoding than for you to just do the transcoding yourself; doing it locally also gives you control over the resolution, bit rate, etc.

When I upload video to youtube, then I have the option to download it as an mp4 file. Material I uploaded at 720p also downloaded at 720p, but at a lower quality setting I think.
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Old 10-19-2011, 09:05 AM
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What is the best freeware program you guys know for video conversion? What is the best non-freeware one? I'm curious.

I tend to find that I lose resolution in video conversion, even if I tell the program to maintain the highest resolution.
I like HandBrake (free).

Last edited by Reply; 10-19-2011 at 09:05 AM..
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  #36  
Old 10-19-2011, 10:06 AM
Doug K. Doug K. is offline
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What is the best freeware program you guys know for video conversion? What is the best non-freeware one? I'm curious.

I tend to find that I lose resolution in video conversion, even if I tell the program to maintain the highest resolution.
If you're working with compressed formats you'll always lose resolution-even if you're just editing and saving in the same format. It gets recompressed each time, throwing away a little more information each time. You'd have to work in an uncompressed format to not lose resolution (which means much larger files).
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Old 10-19-2011, 10:17 AM
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If you're working with compressed formats you'll always lose resolution-...
There are lossy and lossless compression algorithms - so it's not guaranteed you will lose something.
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  #38  
Old 10-19-2011, 12:45 PM
psychonaut psychonaut is offline
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If you're working with compressed formats you'll always lose resolution-even if you're just editing and saving in the same format. It gets recompressed each time, throwing away a little more information each time. You'd have to work in an uncompressed format to not lose resolution (which means much larger files).
Actually, you won't lose resolution (i.e., the physical dimensions of the picture won't change), though if you use a lossy compression algorithm you will lose image quality.
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Old 10-19-2011, 12:51 PM
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If you're working with compressed formats you'll always lose resolution...
I admit i'm not an expert in the terminology of video, although i do use Handbrake for a fair bit of video conversion, and i did stay at a Holiday Inn Express last night.

I'm more familiar with still photography, and when photographers use the term "resolution," they're generally talking about the dimension of the image in pixels. Using this terminology, re-encoding need not result in any loss of resolution. A 720p (1280x720) video will still be 720p after you've compressed it. It might have lost some quality due to the compression, but the resolution will be the same unless you specifically tell your converter to resize the image.

In talking about image quality as a result of compression, photographers are more likely to use terms like quality, compression, artifacts, etc.

Does resolution not mean the same thing in video as it does in still photography?


ETA: Well, while i was typing all that, psychonaut appears to have answered my question.

Last edited by mhendo; 10-19-2011 at 12:51 PM..
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Old 10-19-2011, 03:11 PM
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I admit i'm not an expert in the terminology of video, although i do use Handbrake for a fair bit of video conversion, and i did stay at a Holiday Inn Express last night.
Ok, I have to ask, how does the Holiday Inn factor in?
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Old 10-19-2011, 03:22 PM
Rhythmdvl Rhythmdvl is offline
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Ok, I have to ask, how does the Holiday Inn factor in?
It is well known among many circles that one's tendency to stay at a Holiday Inn Express demonstrates several things--primarily, that I just saved 15 percent on my car insurance by switching to Geico.
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Old 10-19-2011, 03:22 PM
Mahaloth Mahaloth is online now
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I like HandBrake (free).
I always see this one recommended, but I can't seem to get it to work for me. I'm not sure why that is. Does it support pretty much any codec for its conversions?
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Old 10-19-2011, 03:26 PM
mhendo mhendo is online now
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Ok, I have to ask, how does the Holiday Inn factor in?
It's just a riff on a series of silly Holiday Inn Express commercials. In each advertisement, the main character does something surprising or beyond his usual capabilities, and the last line he delivers in the ad is "...but i did stay at a Holiday Inn Express last night."

There's an example here.
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Old 10-19-2011, 03:33 PM
mhendo mhendo is online now
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I always see this one recommended, but I can't seem to get it to work for me. I'm not sure why that is. Does it support pretty much any codec for its conversions?
It will import a whole lot of different formats, from DVD folders to avi files to wmv files, etc.

In terms of output, though, the most recent releases use the MPEG-4, H264, or VP3 (Theora) codec, and will export only as MKV or MP4 files. Earlier versions (up to 0.93) supported the DivX codec and the AVI container, but these were dropped for reasons outlined here:
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AVI is a rough beast. It is obsolete. It does not support modern container features like chapters, muxed-in subtitles, variable framerate video, or out of order frame display. Furthermore, HandBrake's AVI muxer is vanilla AVI 1.0 that doesn't even support large files. The code has not been actively maintained since 2005. Keeping it in the library while implementing new features means a very convoluted data pipeline, full of conditionals that make the code more difficult to read and maintain, and make output harder to predict. As such, it is now gone. It is not coming back, and good riddance.
Handbrake is great for me, because i have an LG Blu-Ray player that offers both DLNA functionality and a USB port, and will comfortably read MKV and MP4 files from either my computer (over the network) or from a USB key.
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