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1. Re: Jerky Motion of MP4 file
Sébastien Périer Sep 9, 2009 5:57 PM (in response to Petrula)What are the specs of your computer ?
CPU, Gpu, ram and gfx card ?
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2. Re: Jerky Motion of MP4 file
Petrula Sep 9, 2009 7:58 PM (in response to Sébastien Périer)Adobe Production Suite CS4
Windows XP Pro SP3
Motherboard: ASUS P4C800-E Deluxe
CPU: Pentium IV 2.53 GHz
RAM: 3GB
ATI Radean 7200 Series AGP
Graphics Chipset: RADEON 7200 SERIES
Current Bus Setting: AGP 4X
Memory Size: 32 MB
DAC: Internal DAC (350MHz)
Memory Type: DDR SGRAM / SDRAM
Core Clock in MHz: 164 MHz
Memory Clock in MHz: 164 MHz
BIOS Version: 001.001.000.055
BIOS Part Number: 113-73701-101
BIOS Date: 2000/08/28
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3. Re: Jerky Motion of MP4 file
Adolfo Rozenfeld Sep 9, 2009 8:37 PM (in response to Petrula)Are you rendering from the Render Queue using one of the H264 presets or are you using the File > Export command?
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4. Re: Jerky Motion of MP4 file
Petrula Sep 9, 2009 9:22 PM (in response to Adolfo Rozenfeld)These are the Render Queue H.264 preset values.
<?xpacket begin="" id="W5M0MpCehiHzreSzNTczkc9d"?>
<x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 4.2.2-c063 53.351735, 2008/07/22-18:11:12 ">
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
<rdf:Description rdf:about=""
xmlns:xmpDM="http://ns.adobe.com/xmp/1.0/DynamicMedia/"
xmlns:stDim="http://ns.adobe.com/xap/1.0/sType/Dimensions#">
<xmpDM:videoFrameSize rdf:parseType="Resource">
<stDim:w>1280</stDim:w>
<stDim:h>720</stDim:h>
<stDim:unit>pixel</stDim:unit>
</xmpDM:videoFrameSize>
<xmpDM:videoFrameRate>29.000000</xmpDM:videoFrameRate>
<xmpDM:videoFieldOrder>Progressive</xmpDM:videoFieldOrder>
<xmpDM:videoPixelAspectRatio>100/100</xmpDM:videoPixelAspectRatio>
<xmpDM:audioSampleRate>48000</xmpDM:audioSampleRate>
<xmpDM:audioSampleType>Compressed</xmpDM:audioSampleType>
<xmpDM:audioChannelType>Stereo</xmpDM:audioChannelType>
</rdf:Description>
</rdf:RDF>
</x:xmpmeta> -
5. Re: Jerky Motion of MP4 file
Adolfo Rozenfeld Sep 9, 2009 9:57 PM (in response to Petrula)Oh, I see.
The thing is, H264 is a very, very efficient compression scheme. But that comes at a cost - H264 is extremely processor intensive for decoding.
A 2.5 Ghz Pentium IV may not have enough power to play H264 video at HD resolutions, and that may be the reason why you get jerky playback.
Other codecs may be a bit less efficient, but easier to handle for the CPU. For example, an On2 VP6-encoded FLV video file (the presets which mention "Flash 8" in their names) could be such a case. If you raise the data rate for local playback (the defaults are more optimized for web delivery) you should get decent quality and your computer should be able to cope.
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6. Re: Jerky Motion of MP4 file
Petrula Sep 9, 2009 11:32 PM (in response to Adolfo Rozenfeld)Thanks for the feedback about why H264 is jerky on my computer.
As you suggested,
I used the FLV preset to create two FLV files.
Codec: FLV4/VP62
Name: Flash/On2 VP6
kbps: 1699
kbps: 5409
Both files work much better than the H264 MP4 file.
The kbps:1699 file is a bit jerky.
The kbps:5409 file is more jerky.
Since the files are on my hard drive, I am not sure why the kbps:5409 is jerkier since that is the rate DVDs play 720x480 movies at. I would expect the kbps:1699 to be of poorer quality because of the lower bandwith.
Just so you know where I am heading. I want to place my 1280x720P HDV/HDTV 720 29.97 square pixel AE composition on Vimeo.
Vimeo recommends "using the H.264 codec at size 1280×720, bit rate 3000-5000 kbits/sec (optimized for “download”), key frame every 30 frames (frame reordering on), using whatever frame rate you shot in. For sound, use AAC at 128kbps in stereo."
By the way, there is a HD video on Vimeo called "FIA GT3 Video Battle" which GSpot says uses
Codec: avc1
Name: H.264/MPEG-4 AVC
Size: 1280 x 720
Frames/s: 23.976
kbps: 1803
I downloaded it to my hard drive. On my computer, it is a slightly jerky but not too bad. Why my video using the same settings is so much jerkier than this video is unclear. Of course, as you explained, I cannot expect a H.264 codec to keep up with my slower computer. It is also unclear if I should Set Key Frame Distance to 30.
Is there a white paper or book that explains in detail the tradeoffs and recommendations for both HD web based and Blue Ray situations like this? Thanks again for your help.
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7. Re: Jerky Motion of MP4 file
Adolfo Rozenfeld Sep 10, 2009 12:34 AM (in response to Petrula)Since the files are on my hard drive, I am not sure why the kbps:5409 is jerkier since that is the rate DVDs play 720x480 movies at. I would expect the kbps:1699 to be of poorer quality because of the lower bandwith.
Petrula: Common sense may seem to suggest that, but common sense is not the only thing there is to it
Data rate is hardly a direct meaure for this. DVDs use MPEG-2 compression, which is much, much lighter to decode in processing terms. it's of course less efficient as well.
Just so you know where I am heading. I want to place my 1280x720P HDV/HDTV 720 29.97 square pixel AE composition on Vimeo.
The good news is that the fact that your computer may not be able to keep up, doesn't mean that the H264 file you originally made won't work. Try uploading it, and if it still doesn't play smoothly from Vimeo, make sure you also try watching it in computer with a more recent CPU. Also, bear in mind that H264 files can be watched using different players, and perhaps one of these players manages to give you smoother playback. You can try the (current) Flash player, Quicktime player and also applications like VLC.
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8. Re: Jerky Motion of MP4 file
techsc Nov 6, 2009 7:11 AM (in response to Petrula)It is a container problem.
If you change the container 'mp41' to 'avc1' the file will play fine.
Use a hex editor (like ultraedit) to change the container info manually.
Change the part "70 C4" into "E6 78". In all my files, this helped. Don't know if it will produce a valid mp4-file, but the play fine now.
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9. Re: Jerky Motion of MP4 file
Mylenium Nov 6, 2009 9:48 AM (in response to techsc)Very interesting. Though I might still add anotehr warning: changing the stream flags may initialze the wrong decoding matrix and produce visual artifacts. So it's still something that should only be done, if all other solutions like using external converters to transcode/ convert to another MPEG flavor or a more conventional media format have failed. Still, great tip.
Mylenium
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10. Re: Jerky Motion of MP4 file
techsc Nov 6, 2009 10:47 AM (in response to Mylenium)You are right.
I am having these issues with Adobe Premiere Pro CS4.
So I have been forced to buy the MainConcept MPEG Pro HD 4 for 150,- EUR.
From my current experience using their mp4-codec, the resulting file plays fine - more tests will have to come.






