AVI Compressor Comparison Example not working with Flame.avi

[MF]

Hello,

I downloaded the NI Vision module for a trial to see what it could do. I will be owrking with black and white files (AVI or other) so I tried the "AVI Compressor Comparison Example.vi" along with the "Flame.avi" from "C:\Program Files\National Instruments\Vision\Examples\Images\AVIs". Basically, the example decompresses "Flame.avi" and then compresses the same file using all of the installed codecs.

When I run the example and then try to play the avi files, all of them are blank (black) and reflect a much shorter playing time than the 16.6 seconds of the original (before decompression) avi which I can play on VLC and QuickTime but not Windows Media Player. When I look at the original video properties in LV, the file format is RGB even though it is B&W. When I look at the video properties in VLC or QuickTime, it shows it as Motion JPEG OpenDML, 200 x 340 with millions of colors.

All of the other avi files in the example folder work fine.  Does anyone have any ideas of what might be going on? Thanks.

Michael Froehlich

I am running LabVIEW 8.5 on a Windows 32 bit XP Service Pack 2 PC.  I have DirectX 9.0c installed.

[BCho]

Hey Michael,

I am a little confused by your post. However, first things first. You can have an image that is of RGB type and it still appear B&W.  So, that Flame.avi file, though it appears B&W, is actually a color picture. Instead of a single numeric value to represent a grey level, there are three numeric values (RGB) that combine to represent a grey level. Possible reasons for this I am not quite sure. It could be to give a larger avi file to better test the different codecs.  In terms of playing the avi files again. This depends on the codecs being used and whether or not the tool you are using to play them supports that particular codec. You had mentioned that the other avi's work fine, particularly, which avi files are you referring to? 

Also, if you manually read in the Flame.avi and then write it again using a codec to compress your avi do you see the same problems introduced by the AVI compressor Comparison Example?

[MF]

Hello Ben,

Thank-you for your reply. I agree the image is an RGB type image (32 bit). All of the AVI files came with the NI Vision module. I can work with the "Side Crash 1" and "Side Crash 2" files fairly well but some of the codecs don't encode the uncompressed file. But let us concentrate on the "flame.avi" file for the moment. 

Straight out of the NI Vision box the example did not work so I took the "flame.avi" file and converted it to various other formats using Super while holding the image size the same. I then tried to use the files with this example. All files output from the example VI contained data but the images were all junk.

I then converted the file to a 720x480 format and things looked good. Maybe there is a size limitation with the example. I do not know.

Have you been successful with this flame.avi and AVI Compressor Comparison Example? Which codecs worked?

Michael

Message Edited by MF on 02-25-2010 08:21 AM

[BCho]

Hey MF,

This AVI Compressor Comparison Example.vi does work on my system for all of the sample videos. The codecs that I have been using are DV Video Encoder, MJPEG, Cinepak Codec by Radius, Intel IYUY, Microsoft RLE, and Microsoft Video 1. In terms of your testing. What codecs have you tried? Also, it seems that after playing with the .AVI file a little you could get the example to run, but when running the actual VI, the video quality was poor.

Do any of the other AVI shipping examples give you trouble? Are you able to create your own AVI from LabVIEW using the AVI VI's? What codecs do you have installed on your system?