rmvb to avi?
rmvb to avi?
Yes, I've tried tons of converters but they never ended up how I wanted to be. >_< I need a freeware that converts 100%. I've tried the whole Virtualdubmod but it didn't work out and I spent hours trying to fix it. So any that can answer my problem? =/ Thanks in advance.
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There are many reasons probably why.
Avi is constant bitrate, which means number of pixels that can hold quality is limited, while RMVB is variable, which means pixels can change the numbers in any form they want, unless you limit it (then it will be limited).
1. Due to this factor, AVI will always have certain size when it is certain time (That's why most videos that is around 1 hour is 700mbs~). However, RMVB does not have such constraints, and it saves sizes, because if picture quality does not require such huge size limit, it will not be save as huge version, which cuts out file redundancy. This is why generally RMVB Videos are smaller then AVI or even MKV counterparts which has been encoded with strict limitations.
2. Also, because of such reason, quality you want to convert will end up lossy, or you will lose some information on the way when you recode. Reason this may be is especially when you realize most video codecs out there are already Lossy, like MP3 (You lose some sound information.) As you should already know, burning MP3 as an Audio CD and then re-ripping into MP3 is disastrous idea. Recoding video is pretty much same thing, unless you know how to adjust things to get what you exactly want.
3. Because of the same reasons, conversion process is even harder, because Real Media holds strict copyright to their codec. There are "open-source" versions, however, but they are technically illegal, and I should mention that due to this factor, not much has been experimented about the codec. There's only Encoder and Decoder, but not Re-encoder. (Or process to do it.)
There are programs that let you do it, though. I can't name some right now because I just can't remember. But it's Real... something... Search more about it in Google, and you should be able to find it.
Quick question: For what reason are you trying to convert?
Avi is constant bitrate, which means number of pixels that can hold quality is limited, while RMVB is variable, which means pixels can change the numbers in any form they want, unless you limit it (then it will be limited).
1. Due to this factor, AVI will always have certain size when it is certain time (That's why most videos that is around 1 hour is 700mbs~). However, RMVB does not have such constraints, and it saves sizes, because if picture quality does not require such huge size limit, it will not be save as huge version, which cuts out file redundancy. This is why generally RMVB Videos are smaller then AVI or even MKV counterparts which has been encoded with strict limitations.
2. Also, because of such reason, quality you want to convert will end up lossy, or you will lose some information on the way when you recode. Reason this may be is especially when you realize most video codecs out there are already Lossy, like MP3 (You lose some sound information.) As you should already know, burning MP3 as an Audio CD and then re-ripping into MP3 is disastrous idea. Recoding video is pretty much same thing, unless you know how to adjust things to get what you exactly want.
3. Because of the same reasons, conversion process is even harder, because Real Media holds strict copyright to their codec. There are "open-source" versions, however, but they are technically illegal, and I should mention that due to this factor, not much has been experimented about the codec. There's only Encoder and Decoder, but not Re-encoder. (Or process to do it.)
There are programs that let you do it, though. I can't name some right now because I just can't remember. But it's Real... something... Search more about it in Google, and you should be able to find it.
Quick question: For what reason are you trying to convert?
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- Posts: 85
- Joined: Jun 8th, '07, 23:48
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This is not correct. AVI can hold variable bitrate video just like any other container format. Every time you do a constant quantizer or 2-pass encoding, the result will be a variable bitrate video stream.FoolyDooly wrote:Avi is constant bitrate, which means number of pixels that can hold quality is limited, while RMVB is variable, which means pixels can change the numbers in any form they want, unless you limit it (then it will be limited).
RMVB files are smaller because the proprietary RealNetworks codec is more efficient than Xvid and DivX which have to adhere to the MPEG-4/ASP specification. As soon as encoders switch from Xvid/DivX to x264 which implements the H.264 standard, the advantage of using RMVB will be gone. See here for a comparison of Xvid vs. x264.1. Due to this factor, AVI will always have certain size when it is certain time (That's why most videos that is around 1 hour is 700mbs~). However, RMVB does not have such constraints, and it saves sizes, because if picture quality does not require such huge size limit, it will not be save as huge version, which cuts out file redundancy. This is why generally RMVB Videos are smaller then AVI or even MKV counterparts which has been encoded with strict limitations.
RMVB is difficult to transcode into something else because it was designed to lock you into RealNetworks products. If RealNetworks goes out of business and leaves RealPlayer behind without updates, RMVB files will become useless. It's a perfect example of vendor lock-in. That's why open standards are so important. RMVB should be avoided whenever possible.
meh, im still surprised how efficient RealMedia's RealVideo Video Codec is.
however its so annoying that the video is locked so strongly to a certain codec that transcoding it from one format to another results in definite quality loss
(without any special handling or TLC).
i've noticed that in order to produce the higheset quality conversion (maybe around 85-95% quality contained),
i'd have to maybe use approximately 100% more of a file size for XviD/DivX,
and around 50% extra for H.264/x264 (i hope that makes sense)
ex: 300mb rmvb = 450mb x264 = 600mb xvid
at least, those are the results that i achieve in my own experiments
p.s.: i still like my rmvb->avi method [Here],
which is basically an offshoot of the tutorial from http://forum.videohelp.com/topic289872.html
however, i forgot to specify forcing the framerate conversion that you can see above.
however its so annoying that the video is locked so strongly to a certain codec that transcoding it from one format to another results in definite quality loss
(without any special handling or TLC).
i've noticed that in order to produce the higheset quality conversion (maybe around 85-95% quality contained),
i'd have to maybe use approximately 100% more of a file size for XviD/DivX,
and around 50% extra for H.264/x264 (i hope that makes sense)
ex: 300mb rmvb = 450mb x264 = 600mb xvid
at least, those are the results that i achieve in my own experiments
p.s.: i still like my rmvb->avi method [Here],
which is basically an offshoot of the tutorial from http://forum.videohelp.com/topic289872.html
however, i forgot to specify forcing the framerate conversion that you can see above.
You mentioned you tried the whole VirtualDubMod thing, but there's more than one way of doing it.
I have successfully transcoded RMVB to a usable format using:
Real Alternative (DirectShow filter): http://www.free-codecs.com/download/Rea ... native.htm
Avisynth: http://downloads.sourceforge.net/avisyn ... g_mirror=0
Then you write an Avisynth script with:
DirectShowSource("your_file_path.rmvb")
Open that script with VirtualDubMod and you should be able to encode it accurately.
There's always a free way of doing things. The problem is that it usually is slightly more complicated than the pay methods.
I have successfully transcoded RMVB to a usable format using:
Real Alternative (DirectShow filter): http://www.free-codecs.com/download/Rea ... native.htm
Avisynth: http://downloads.sourceforge.net/avisyn ... g_mirror=0
Then you write an Avisynth script with:
DirectShowSource("your_file_path.rmvb")
Open that script with VirtualDubMod and you should be able to encode it accurately.
There's always a free way of doing things. The problem is that it usually is slightly more complicated than the pay methods.
Super does work w/ rmvb to avi, I've done it before but it doesn't work w/ everyfile though.
Vdubmod is the easiest and always works for me. The thing I found out is that vdubmod doesn't support asian language fonts(maybe why some people say it doesn't work since usually chinese files use rmvb), the files HAVE to be in English for it to recognize properly to convert it into .avi w/ xvid or divx codec. You need the avisynth files also to convert rmvb to avi. I posted that on some other thread about rmvb to avi but I'm too lazy right now to look for it. Search for yourself, I also posted a link to a tutorial on how to convert from rmvb to avi in that thread.
Vdubmod is the easiest and always works for me. The thing I found out is that vdubmod doesn't support asian language fonts(maybe why some people say it doesn't work since usually chinese files use rmvb), the files HAVE to be in English for it to recognize properly to convert it into .avi w/ xvid or divx codec. You need the avisynth files also to convert rmvb to avi. I posted that on some other thread about rmvb to avi but I'm too lazy right now to look for it. Search for yourself, I also posted a link to a tutorial on how to convert from rmvb to avi in that thread.
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