VDJ Ron
MP4 using the H.264 codec and aac audio produces the best quality videos, however...suppose variable bitrate encoding is used. This could produce huge data spikes which could freeze a HD MP4 video. Xvid does not suffer from this problem, especially with high quality constant bitrate video (@2000kb/s), and the audio can be excellent (mp3 at 320kb/s). Surely Xvid must be better for older computers?
Comments.
Comments.
发表时间 Mon 31 Oct 16 @ 4:55 pm
Adion
Pretty much all video codecs use a variable bitrate, and most encoders have settings to limit the maximum bitrate exactly so that it is suitable for streaming over limited bandwidth connections for example.
I'm not sure if there's a strong or significant relation between bitrate and decoder performance.
If you must do video dj'ing on a very old computer but still at full hd then I guess mp3/h263 (xvid) will use a bit less cpu power compared to aac/h264 (mp4)
Most recent computers (let's say in the past 5 years or so) can also use the gpu to aid in decoding mp4 however, so for full hd that will not be an issue and there will be more than sufficient power to decode them.
I'm not sure if there's a strong or significant relation between bitrate and decoder performance.
If you must do video dj'ing on a very old computer but still at full hd then I guess mp3/h263 (xvid) will use a bit less cpu power compared to aac/h264 (mp4)
Most recent computers (let's say in the past 5 years or so) can also use the gpu to aid in decoding mp4 however, so for full hd that will not be an issue and there will be more than sufficient power to decode them.
发表时间 Mon 31 Oct 16 @ 5:30 pm
VDJ Ron
Hm..I noted that Locodog expressed a wish for a laptop made during this decade, I'm in a similar position.
Other factors enter into this issue such as how far the video is traveling. In my case it's often 150ft.
I specify a constant bitrate of 2500kb/s for my Xvid videos and audio mp3 320kb/s.
I suspect anything above 2000kb/s makes little difference, except maybe in high action scenes.
Compression is not so critical nowadays due to the large size of our hdd.
I'm not sure if there's a strong or significant relation between bitrate and decoder performance.
I think it's exponential hence going to a limit. In the lower bitrate regions it may well be steep linear.
Other factors enter into this issue such as how far the video is traveling. In my case it's often 150ft.
I specify a constant bitrate of 2500kb/s for my Xvid videos and audio mp3 320kb/s.
I suspect anything above 2000kb/s makes little difference, except maybe in high action scenes.
Compression is not so critical nowadays due to the large size of our hdd.
I'm not sure if there's a strong or significant relation between bitrate and decoder performance.
I think it's exponential hence going to a limit. In the lower bitrate regions it may well be steep linear.
发表时间 Mon 31 Oct 16 @ 5:43 pm
A Man and His Music
I bought a computer from the family of the guy that got me into computer Djing, after he passed away. This was in 2005. There are a lot of AVI vids on the hard drives. I found that they have, I don't know what you would call it, but I say pixilation. I delete them and replace.
发表时间 Mon 31 Oct 16 @ 5:48 pm
VDJ Ron
AMAHM it's down to the encoding bitrate, and other options. Xvid produces a larger file size than MP4 for an equal picture quality. I could encode rubbish MP4!
Your Xvids were no doubt no good.
Your Xvids were no doubt no good.
发表时间 Mon 31 Oct 16 @ 5:55 pm
A Man and His Music
Who is providing video in AVI?
发表时间 Mon 31 Oct 16 @ 5:57 pm
VDJ Ron
We can make are own in many ways.
Any video can be attached to a mp3 audio file.
I'm starting to think that HD video will choke the life out of many older computers.
HD 1080i video often has bitrates a factor of 10 or more higher than Xvid.
Could it be wise under some circumstances to down grade a HD MP4 video file?
Any video can be attached to a mp3 audio file.
I'm starting to think that HD video will choke the life out of many older computers.
HD 1080i video often has bitrates a factor of 10 or more higher than Xvid.
Could it be wise under some circumstances to down grade a HD MP4 video file?
发表时间 Mon 31 Oct 16 @ 7:01 pm
Adion
bigron1 wrote :
I'm not sure if there's a strong or significant relation between bitrate and decoder performance.
I think it's exponential hence going to a limit. In the lower bitrate regions it may well be steep linear.
I think it's exponential hence going to a limit. In the lower bitrate regions it may well be steep linear.
I don't know if that is true (no idea how you measured and came to that conclusion), but if it is all the more reason to use h264, since you can get the same quality with a lower bitrate.
Anyway, with just speculation this thread is not very useful.
Since you are already in the process of encoding your own videos, why not simply try it yourself?
Experiment with higher bitrates, encode the same video with mp4 and xvid and check cpu usage or problems while playing them back.
The Core 2 Duo line of cpu's was released in 2006 I see, I would think that would be sufficient for decoding of h264 streams, and that seems to be backed up by these benchmarks:
http://forum.doom9.org/showthread.php?t=159486
The benchmark uses Full HD clips at between 10Mbps and 40Mbps (!) and still they decode at 50 up to 90fps on a core 2 duo (so enough processing power to decode at least 2 videos at the same time)
With bitrates more commonly used for video clips I don't think it's going to be any problem.
Also, if you do your own encoding, a constant bitrate is fairly useless. What you are typically looking for is constant quality. With the x264 encoder this is called CRF (constant rate factor)
You just find a value that you are happy with once and you can keep using that value. If the clip is low in motion you will not waste disk space since less bandwidth is required for the given quality, but if it's high in motion it will use more bandwidth at these parts keeping the quality at the level you expect.
发表时间 Mon 31 Oct 16 @ 7:17 pm
VDJ Ron
I don't know if that is true (no idea how you measured and came to that conclusion).
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
but if it is all the more reason to use h264, since you can get the same quality with a lower bitrate
H'm I was thinking that..but I've been happy with single pass 2500kb/s Xvid with 320kb/s mp3 audio which encodes rapidly, and works well.
Sometimes encoding is like watching paint dry.
At the moment I'm investigating all the aspects of video which are within my capabilities.
I have much to learn.
The benchmark uses Full HD clips at between 10Mbps and 40Mbps (!) and still they decode at 50 up to 90fps on a core 2 duo (so enough processing power to decode at least 2 videos at the same time)
The above is the kind of interesting comment I'm looking for, and the Intel dual core CPU's are not that bad!
waste disk space
This is not important for the moment.
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
but if it is all the more reason to use h264, since you can get the same quality with a lower bitrate
H'm I was thinking that..but I've been happy with single pass 2500kb/s Xvid with 320kb/s mp3 audio which encodes rapidly, and works well.
Sometimes encoding is like watching paint dry.
At the moment I'm investigating all the aspects of video which are within my capabilities.
I have much to learn.
The benchmark uses Full HD clips at between 10Mbps and 40Mbps (!) and still they decode at 50 up to 90fps on a core 2 duo (so enough processing power to decode at least 2 videos at the same time)
The above is the kind of interesting comment I'm looking for, and the Intel dual core CPU's are not that bad!
waste disk space
This is not important for the moment.
发表时间 Mon 31 Oct 16 @ 7:31 pm
Adion
bigron1 wrote :
I don't know if that is true (no idea how you measured and came to that conclusion).
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
But one that does not hold true for many computer algorithms.
There are many algorithms for which there is a trade off between using memory and doing less computation, or using less memory but doing more computation.
In the case of a video encoder, it might be the case that if you increase the bitrate, the encoder decides that it's better for the quality to simply insert a high quality key-frame (like a jpg) instead of using previous frames and describing how to get from the previous frames to the current one.
It's likely that simply decoding key frames uses less processing power compared to calculating motion vectors etc...
The only way to truly know is to do proper benchmarks.
Quote :
H'm I was thinking that..but I've been happy with single pass 2500kb/s Xvid with 320kb/s mp3 audio which encodes rapidly, and works well.
Sometimes encoding is like watching paint dry.
I'm investigating all the aspects of video which are within my capabilities at the moment.
I have much to learn.
Sometimes encoding is like watching paint dry.
I'm investigating all the aspects of video which are within my capabilities at the moment.
I have much to learn.
If you have a somewhat recent graphics adapter you may want to learn about mp4 encoders that use the gpu to do the bulk of their work.
They are capable of delivering higher quality at lower bitrate, and at speeds over 10x real-time.
发表时间 Mon 31 Oct 16 @ 7:43 pm
VDJ Ron
I don't know if that is true (no idea how you measured and came to that conclusion).
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
It wasn't just a generalization.
I've been gradually increasing the video bitrate and observing the effect. With AVI Xvid there are rapid linear improvements in quality up to around 1500kb/s, after this the improvements tail off, and anything above 2500kb/s has little effect. That reminded me of growth to a limit. The word exponential is wrong, I've forgot the name of the mathematical model.
Logarithmic Model
y = a + b ln x
Features
Increases without bound to right
Very rapid growth, followed by slower growth,
Hm I'm getting old and so are my laptops. One day I'll get a new one.
Just a generalization Adion. The greater the effort expended the less the return. Its common within the laws of nature.
It wasn't just a generalization.
I've been gradually increasing the video bitrate and observing the effect. With AVI Xvid there are rapid linear improvements in quality up to around 1500kb/s, after this the improvements tail off, and anything above 2500kb/s has little effect. That reminded me of growth to a limit. The word exponential is wrong, I've forgot the name of the mathematical model.
Logarithmic Model
y = a + b ln x
Features
Increases without bound to right
Very rapid growth, followed by slower growth,
Hm I'm getting old and so are my laptops. One day I'll get a new one.
发表时间 Mon 31 Oct 16 @ 7:56 pm
A Man and His Music
It would seem that getting a new computer, would be a better bet. It's like putting push to start, and every other new convenience in a 1980 car. A waste of time and money. Time is something that none of us have, stop wasting it.
发表时间 Mon 31 Oct 16 @ 8:40 pm
VDJ Ron
So.. two video files, both sized 67mb, one AVI Xvid, the other MP4 H264 extracted from an average DVD
On a new 42" TV I could not see any significant difference. Remember this is not HD material.
The MP4 file took 15min to encode while the AVI 2min.
I made a mistake in the MP4 audio settings leaving AAC at 128kb/s. I therefore expected very poor sound.
AVI Xvid is stiill a good format when HD is not a requirement, which is the case for the bulk of the worlds music.
The slower MP4 encoding times are a disadvantage.
AVI Xvid is still a viable video codec.
On a new 42" TV I could not see any significant difference. Remember this is not HD material.
The MP4 file took 15min to encode while the AVI 2min.
I made a mistake in the MP4 audio settings leaving AAC at 128kb/s. I therefore expected very poor sound.
AVI Xvid is stiill a good format when HD is not a requirement, which is the case for the bulk of the worlds music.
The slower MP4 encoding times are a disadvantage.
AVI Xvid is still a viable video codec.
发表时间 Tue 01 Nov 16 @ 9:28 pm
mp3jrick
A Man and His Music wrote :
It's like putting push to start, and every other new convenience in a 1980 car.
Unless the battery is dead with a standard trans, very useful in that case....lol
There was a time when all of these codecs battled for the lead.... mp4 h264 won that battle long ago and is the standard of today imo.
Shooting video @ 150' is kind of ridiculous just with light loss alone imo...
I don't want to argue with you
发表时间 Tue 01 Nov 16 @ 10:19 pm
VDJ Ron
MP4 is the standard being put forward to combine with new technology, and is also probably eminently suited to DRM.
What if you have an old laptop?
I'm not thinking about this from the point of view of those who have the latest, and greatest technology.
Many use laptops which are older than 5 years.
MP4 H264 won the codec war @ 4 years ago.
Things made @ 2010 are not rubbish because they are 6 years old.
There is another important point.
DJ's are compelled to use material created prior to the creation of HD.
The movie industry however is very much at the forefront of HD.
It's my belief the movie industry demands standards suitable for themselves..not the DJ.
What if you have an old laptop?
I'm not thinking about this from the point of view of those who have the latest, and greatest technology.
Many use laptops which are older than 5 years.
MP4 H264 won the codec war @ 4 years ago.
Things made @ 2010 are not rubbish because they are 6 years old.
There is another important point.
DJ's are compelled to use material created prior to the creation of HD.
The movie industry however is very much at the forefront of HD.
It's my belief the movie industry demands standards suitable for themselves..not the DJ.
发表时间 Tue 01 Nov 16 @ 10:30 pm
mp3jrick
As it happens I am running a 2009 17" MBP dual core and works flawlessly.
I run 4k projectors on 9x12 screens with no issues.
I run 4k projectors on 9x12 screens with no issues.
发表时间 Tue 01 Nov 16 @ 10:39 pm
VDJ Ron
Anyway I'll keep on testing video from the point of view of a DJ with older equipment.
I see no need for a new laptop at the moment.
My Win10 Pro 64bit, Intel dual core 2.4ghz cpu, 5gb memory, and 1000gb hdd is doing quite well!
I think you've been doing this sort of stuff for a long time Rick, I'm just beginning. I find looking at the history of video, and the DJ interesting.
I see no need for a new laptop at the moment.
My Win10 Pro 64bit, Intel dual core 2.4ghz cpu, 5gb memory, and 1000gb hdd is doing quite well!
I think you've been doing this sort of stuff for a long time Rick, I'm just beginning. I find looking at the history of video, and the DJ interesting.
发表时间 Tue 01 Nov 16 @ 10:52 pm
the SOUND INSURGENT
MP4 H.264 .......Ftw.
If your just doing "Basic" playback which I assume your doing because I don't see you as a scratch DJ I highly doubt your gonna see any difference between the 2.
Also some programs wont even play MP4's such as Resolume.
Theres reason why MP4's are king........
Keep researching, you'll eventually find the answer.
If your just doing "Basic" playback which I assume your doing because I don't see you as a scratch DJ I highly doubt your gonna see any difference between the 2.
Also some programs wont even play MP4's such as Resolume.
Theres reason why MP4's are king........
Keep researching, you'll eventually find the answer.
发表时间 Tue 01 Nov 16 @ 11:43 pm
VDJ Ron
AVI vs MP4: The Difference Between AVI and MP4
AVI vs MP4 - Proprietor/Developer
AVI: Microsoft
MP4: MPEG (Motion Pictures Expert Group)
AVI vs MP4 - Video Formats Supported
AVI: Almost anything through VFW (Video for Windows)
MP4: MPEG-2 Part 2, MPEG-4 ASP, H.264/MPEG-4 AVC, H.263, VC-1, Dirac, others
AVI vs MP4 - Audio Formats Supported
AVI: Almost anything through ACM (Audio Compression Manager)
MP4: MPEG-2/4 (HE)-AAC, MPEG-1/2 Layers I, II, III (MP3), AC-3, Apple Lossless (ALAC), ALS, SLS and others
AVI vs MP4 - Supported Codecs
AVI: Often DivX, Xvid
MP4: MPEG-4 and H.264 video codecs
AVI vs MP4 - Supported Devices
AVI: Microsoft devices, Game consoles, but not compatible with Apple devices
MP4: PC, Mac, all kinds of mobile devices as iPhone iPad Android, etc.
AVI vs MP4 - Supported Media Players
AVI: Windows Media Player or other Windows-based players
MP4: Almost all kinds of media players
Advice: Both AVI and MP4 are media containers and they can store many kinds of video codecs. Hence, when comparing AVI to MP4, we should compare their video audio codecs, but not the media container itself. Though both AVI and MP4 are most widely used video formats, need to mention that MP4 has a better quality in a same size and MP4 is more compatible. MP4 can be played on more devices and media players than AVI. Besides, MP4 can also easily stream on the Internet while AVI can't. Thus, ripping DVD to MP4 would be a good choice with a professional DVD to MP4 converter.
I suppose the above is a reasonable assessment of the situation.
Hm.. I didn't realize Microsoft started AVI, that's a +1 on a laptop, maybe a -1 on a Mac.
AVI vs MP4 - Proprietor/Developer
AVI: Microsoft
MP4: MPEG (Motion Pictures Expert Group)
AVI vs MP4 - Video Formats Supported
AVI: Almost anything through VFW (Video for Windows)
MP4: MPEG-2 Part 2, MPEG-4 ASP, H.264/MPEG-4 AVC, H.263, VC-1, Dirac, others
AVI vs MP4 - Audio Formats Supported
AVI: Almost anything through ACM (Audio Compression Manager)
MP4: MPEG-2/4 (HE)-AAC, MPEG-1/2 Layers I, II, III (MP3), AC-3, Apple Lossless (ALAC), ALS, SLS and others
AVI vs MP4 - Supported Codecs
AVI: Often DivX, Xvid
MP4: MPEG-4 and H.264 video codecs
AVI vs MP4 - Supported Devices
AVI: Microsoft devices, Game consoles, but not compatible with Apple devices
MP4: PC, Mac, all kinds of mobile devices as iPhone iPad Android, etc.
AVI vs MP4 - Supported Media Players
AVI: Windows Media Player or other Windows-based players
MP4: Almost all kinds of media players
Advice: Both AVI and MP4 are media containers and they can store many kinds of video codecs. Hence, when comparing AVI to MP4, we should compare their video audio codecs, but not the media container itself. Though both AVI and MP4 are most widely used video formats, need to mention that MP4 has a better quality in a same size and MP4 is more compatible. MP4 can be played on more devices and media players than AVI. Besides, MP4 can also easily stream on the Internet while AVI can't. Thus, ripping DVD to MP4 would be a good choice with a professional DVD to MP4 converter.
I suppose the above is a reasonable assessment of the situation.
Hm.. I didn't realize Microsoft started AVI, that's a +1 on a laptop, maybe a -1 on a Mac.
发表时间 Wed 02 Nov 16 @ 12:03 am
VDJ Ron
mp4 is newer, supports chapers, menus, etc. avi doesn't.
Xvid is just an MPEG-4 Part 2 video codec. mp4 is the offical MPEG-4 container and is actually Part 14. So Xvid != mp4 either.
Typically avi is used for Xvid video and mp3 audio, however it is more of a general purpose container and could contain basically anything. For Xvid/VBR mp3, mp4 should offer lower overhead than avi, allowing for slightly higher bitrates. The avi will probably offer better compatibility though.
So to sum up, overall mp4 is the better container. Doesn't make it better for all purposes though.
I'm thinking Xvid is fine for an oldish Windows based laptop. Even the incorporated high quality mp3 is adequate.
Very interesting.
I didn't even realize that there had been a codec war until recently.
Encoding to AVI Xvid on a Windows laptop may be close to 10x faster than a MP4 H264 !?
Just as a addon Avidemux is excellent freeware which can often trim/edit video files without re-encoding !
!!!!!FAST!!!!!
Xvid is just an MPEG-4 Part 2 video codec. mp4 is the offical MPEG-4 container and is actually Part 14. So Xvid != mp4 either.
Typically avi is used for Xvid video and mp3 audio, however it is more of a general purpose container and could contain basically anything. For Xvid/VBR mp3, mp4 should offer lower overhead than avi, allowing for slightly higher bitrates. The avi will probably offer better compatibility though.
So to sum up, overall mp4 is the better container. Doesn't make it better for all purposes though.
I'm thinking Xvid is fine for an oldish Windows based laptop. Even the incorporated high quality mp3 is adequate.
Very interesting.
I didn't even realize that there had been a codec war until recently.
Encoding to AVI Xvid on a Windows laptop may be close to 10x faster than a MP4 H264 !?
Just as a addon Avidemux is excellent freeware which can often trim/edit video files without re-encoding !
!!!!!FAST!!!!!
发表时间 Wed 02 Nov 16 @ 12:18 am
