Uncompressed AVI to WMV @ 30fps cannot seem to get smooth video...

[neilcooper33]

Hi all....

I have had this problem for some time and never managed to solve it.... any help would be greatfully recieved

the problem seems to come when i try to create 30fps video, 24fps is ok.

when i compress the video at 30fps, the playback of the resulting WMV file isnt smooth, there are small jerks in the video which dont seem to happen at the same portion of the video when repeat playing the video.

this is the process i currently use...

I work in 3D studio max 2010 to create visualisations,
do some compositing in adobe premiere v2.0 save out as an Uncompressed avi
use windows media encder x64 to create a wmv,
i have tried numerous settings in windows media encoder and seem to get the same result..... lower bitrates help but dont entirely solve, i also want to retain as much quality as i can for the 30fps video....

if anyone has any ideas, please share....

thanks in advance

Neil

[poisondeathray]

what are you computer specs ? if lower bitrates help, this sounds like a playback issue (computer too slow ?)

dimensions of video ?

what format did you import into premiere ?

what dimensions , fps did you export the uncompressed avi as ?

[El Heggunte]

Regardless of how powerful your PC is (or is not), the only way to avoid dropped/duplicated frames with the WMV codecs is by encoding in two-pass mode ++ unconstrained maximum bitrate.

If you're using the infamous "encoding profiles", forget them ---
--- because they are "evil" .

[jagabo]

When the bitrate gets too high for the selecte profile in WMV files frames are dropped to reduce the bitrate requirement. So a 30 fps video will be reduced to 15 fps (possibly even lower) during high bitrate shots. That may, or may not, bet what's going on.

[neilcooper33]

Hi

thanks for the replies!!

i dont think it's specs which are the problem, and i need the video to run on pcs with much lower spec than mine if possible....

ok here goes....

resolution 1024 x 576
imported individual frames into premiere (png files)
i created a 30fps uncompressed avi, and then compressed this using windows media encoder at 30fps also....

yes, the slowdown is generally when there is more movement in the video...

my pc, quad core xeon 3.2ghz, quadro fx 4500 graphics, windows xp, 4gb ram, running 3gb switch,

today i did various tests, i have found that 2 pass mode gives a better result.... can you explain what you mean by unconstained bitrate please El Heggunte? do you mean dont use CBR constant bit rate.... this is what i have been using...

windows media video 9
keyframe interval - 8
frame rate - 30
decoder complexity - Main
video smoothness - 90 (i think, will check when at work tomorrow)
Buffer size - 5 (i think, will check when at work tomorrow)

thanks again people!

Neil

[El Heggunte]

windows media video 9
1024x576
30fps

Those specs shall not be a problem for any PC greater than a 1.5GHz Pentium 4 with an obsolete AGP card.

keyframe interval - 8

frame rate - 30

decoder complexity - Main

video smoothness - 90
Buffer size - 5 <-- So you're using the wrong type of 2-pass...

In the window "Session Properties", goto the tab "Compression", and in the field "Destination", select the option "File Download"; now, click the "Edit" button; DON'T CHANGE the "Video Mode" (Bit rate VBR), and tweak the other parameters as needed.

Good-luck, and have fun!

[jagabo]

can you explain what you mean by unconstained bitrate please El Heggunte?

In a variable bitrate encoding some shots will get more bitrate, some less. "Unsconstrained bitrate" means there will be no artificial limit on the maximim bitrate used for shots that need lots of bitrate. "Constrained bitrate" means there will be a limit placed on the maximum bitrate even if more was required to maintain quality (for example, a particular device may only be able to handle up to a certain bitrate so you have to constrain the bitrate for that device).

do you mean dont use CBR constant bit rate.... this is what i have been using...

You shouldn't use constant bitrate encoding if you're looking for quality -- unless you're willing to go with astronomical bitrates.

[neilcooper33]

thanks again for the info everyone....

OK, giving it a go again today... the only reason i had been using CBR is because i had been running Gspot on examples of videos which seem to run well.... and getting the bit rates / compression technique from the results.... i realise now that is not the way to go.... will let u know how i get on....

cheers

Neil

[neilcooper33]

Hi All

thanks again for your help with this.....

OK, i have tried the following settings.... (i've changed the output from adobe premiere and output from WME to 29.97 to see if that made any difference)

Video encoding mode: Bit rate VBR
Audience: 6009 Kbps
Video codec: Windows Media Video 9
Video bit rate: 6000 Kbps
Video size: Same as video input
Frame rate: 29.97 fps
Key frame: 8 s

unfortunately i am having the same problem....

i read on a forum that a setting which i was using in adobe premiere can cause problems 'optimise stills' i have turned this off but am still getting the same problem.....

here is an output from Gspot for the resulting WMV file.... (i've deleted any fields which were blank...)

FILE_NAME extract_02.wmv
FILE_NAME_WITH_PATH C:\Documents and Settings\coo31768\Desktop\extract_02.wmv
FILE_SIZE 38,649,856
CONT_BASETYPE ASF (.WMA/.WMV)
CONT_TOTAL_BITRATE 0
VIDEO_BITRATE 8223
VIDEO_CODEC_NAME WMP v9 (VC-1 Simple/Main)
VIDEO_CODEC_STATUS Codec Status Undetermined
VIDEO_CODEC_TYPE WMV3
VIDEO_DURATION 0:53.983
VIDEO_SAR 1.778
VIDEO_SIZE_X 1024
VIDEO_SIZE_Y 576

[neilcooper33]

and this is the Gspot output for the uncompressed avi which i get from adobe premiere.....

FILE_NAME extract_02.avi
FILE_SIZE 2,703,831,288
CONT_BASETYPE AVI(.AVI)
CONT_BYTES_MISSING 0
CONT_SUBTYPE Multipart OpenDML AVI (2 parts),
CONT_TOTAL_BITRATE 0
VIDEO_BITRATE 424251
VIDEO_CODEC_NAME BI_RGB Raw Bitmap
VIDEO_CODEC_STATUS No Codec Required
VIDEO_CODEC_TYPE (_RGB)
VIDEO_DAR 1.778
VIDEO_DURATION 0:50.985
VIDEO_FRAME_COUNT 1528
VIDEO_FRAMES_PER_SEC 29.970
VIDEO_PAR 1.000
VIDEO_PICS_PER_SEC 29.970
VIDEO_QF 24.000
VIDEO_SAR 1.778
VIDEO_SIZE_X 1024
VIDEO_SIZE_Y 576

[jagabo]

What is the frame rate of your source? If you're changing frame rates, why? Most video editors simply duplicate or decimate frames to change frame rate. This causes little jerks at regular intervals. For example, going from 24 fps to 30 fps, every 4th frame is duplicated, leading to six little jerks every second.

[neilcooper33]

Hi,

sorry, i'm not actually changing the framerate of the video, i was just testing a render out of premiere at 29.97fps instead of 30fps, just to see if the video was any smoother, but it wasnt..... i'm not using any video as an input in adobe premiere, only a series of images as png files... sorry for the confusion..

Neil

[neilcooper33]

i've just noticed that the uncompressed avis in Gspot are Multipart OpenDML AVI (2 parts)
(1213 frames in first part, 315 frames follow) and also noticed the difference of the video duration.....

uncompressed avi... 0:50.985
wmv... 0:53.983

not sure what this means though....

cheers

Neil

[jagabo]

The original AVI spec had a file size limit of 4GB. Many programs had problems once the size went over 2 GB. The ODML extensions allowed for larger file sizes. I don't know why your running times are different.

I think you're going to have to upload some samples.

Your uncompressed AVI file probably won't play smoothly on your computer because of the high disk I/O requirement. 1024x576 uncompressed 24 bit RGB at 30 fps requires about 53 MB/s of sustained throughput. You can use an editor to step through the video frame by frame to verify there are no missing or duplicate frames. VirtualDub is handy for this.

[neilcooper33]

Hi Jagabo...

thanks for the reply.....

i wasnt trying to play the uncompressed avi, i realise that this is not pratical... it's the wmv i'm struggling with....

i will see if i can get an example uploaded, unfortuantely i cant up load this example as its not in the public domain.....

i'm now trying to export from premiere in a different way, 'uncompressed microsoft avi' instead of 'microsoft avi' with compression set to 'none'

thanks again

Neil

[poisondeathray]

why don't you try exporting wmv directly from pp ?

[neilcooper33]

why don't you try exporting wmv directly from pp ?

i have done this previously, with similar results, ie. not smooth video... do you think this way should be better? i supposed it takes the uncompressed avi out of the equation....

cheers

N

[poisondeathray]

The discrepancy in duration doesn't make sense

Did you examine both the uncompressed avi, and wmv frame by frame (e.g. in vdub) as jagabo suggested ? Looking specifically for blank or duplicated frames

What does mediainfo say about the exported wmv (view=>text) ?

If you render some other low overhead format e.g. xvid , and that plays fine, you can narrow down the problem to being wmv or some setting used by your wmv encoder

Have you tried other playback software? e.g. smplayer, mpchc, kmplayer

[neilcooper33]

The discrepancy in duration doesn't make sense
Did you examine both the uncompressed avi, and wmv frame by frame (e.g. in vdub) as jagabo suggested ? Looking specifically for blank or duplicated frames

thanks, i dont get the unsmooth playback at the same time when replaying the video, so this should discount repeat frames....

the uncompressed avi... mediainfo

General
Complete name : C:\Documents and Settings\coo31768\Desktop\extract_02.avi
Format : AVI
Format/Info : Audio Video Interleave
Format profile : OpenDML
File size : 2.52 GiB
Duration : 50s 984ms
Overall bit rate : 424 Mbps
Video
ID : 0
Format : RGB
Codec ID : 0x00000000
Codec ID/Info : Basic Windows bitmap format. 1, 4 and 8 bpp versions are palettised. 16, 24 and 32bpp contain raw RGB samples
Duration : 50s 984ms
Bit rate : 424 Mbps
Width : 1 024 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Bit depth : 8 bits
Bits/(Pixel*Frame) : 24.000
Stream size : 2.52 GiB (100%)

the wmv... mediainfo

General
Complete name : C:\Documents and Settings\coo31768\Desktop\extract_02.wmv
Format : Windows Media
File size : 36.9 MiB
Duration : 50s 983ms
Overall bit rate mode : Variable
Overall bit rate : 6 065 Kbps
Maximum Overall bit rate : 8 223 Kbps
Encoded date : UTC 2010-09-21 09:45:06.223

Video
ID : 1
Format : VC-1
Format profile : MP@HL
Codec ID : WMV3
Codec ID/Info : Windows Media Video 9
Codec ID/Hint : WMV3
Description of the codec : Windows Media Video 9 - Professional
Duration : 50s 984ms
Bit rate mode : Variable
Bit rate : 6 000 Kbps
Width : 1 024 pixels
Height : 576 pixels
Display aspect ratio : 16:9
Frame rate : 29.970 fps
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.339
Stream size : 36.5 MiB (99%)
Language : English (GB)

I will try an xvid format......

I've tried playing the video in media player classic - i put the statistic on, and it doesnt actually say that there is any frames dropped when i see the slight glitches in the video....

ive also tried in VLC, strangely i cant seem to skip through the video, ie. if i drag the slider across, the video just hangs

thanks again people.... i'm now downloading the latest version of adobe premiere to see if that helps...

cheers

N

[El Heggunte]

Possibly the problem is in WME itself. :–\
I am pretty sure the settings I've recommended
do work as expected in Nic's GUI for the WMV codecs ( WmNicEnc ),
and in the WM Encoding Script ( wmcmd.vbs ) as well.
However, this latter is a command-line application,
and WmNicEnc does require .AVS files as input.

[jagabo]

thanks, i dont get the unsmooth playback at the same time when replaying the video

So are you getting smooth playback or not?

[poisondeathray]

thanks, i dont get the unsmooth playback at the same time when replaying the video

So are you getting smooth playback or not?

I think he's saying the jerkiness isn't repeatable (it occurs at different locations, different timecodes when played on separate occasions) - so it's not likely something encoded into the video

there are small jerks in the video which dont seem to happen at the same portion of the video when repeat playing the video.

[jagabo]

I've tried playing the video in media player classic - i put the statistic on, and it doesnt actually say that there is any frames dropped when i see the slight glitches in the video....

Try different output devices. View -> Options -> Playback -> Output -> DirectShow Video. You have to exit MPCHC and restart it for the change to take place.

[neilcooper33]

thanks, i dont get the unsmooth playback at the same time when replaying the video

So are you getting smooth playback or not?

I think he's saying the jerkiness isn't repeatable (it occurs at different locations, different timecodes when played on separate occasions) - so it's not likely something encoded into the video

there are small jerks in the video which dont seem to happen at the same portion of the video when repeat playing the video.

thanks that's exactly what i mean, sorry for not being clear on that