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View Full Version : my first matrices comparison


SiXXGuNNZ
20th August 2004, 21:51
edit: I am going to redo the test with q2, 750 and 1500, when I get done I will repost the link

thanks to Soulhunter and Manao for making this a little bit easier.

I just que'd up my encodes, when I get home I will que up my compare PSNR and SSIM scripts, then I will pull some screen grabs and repost :)

Soulhunter
20th August 2004, 22:46
For some reason I cant switch between the matrix samples (Firefox 0.9.3) ... :(


EDIT:

Sorry, my fault... It works perfectly !!!


Bye

Manao
20th August 2004, 22:50
At first sight, I would have said it was useless, because you were comparing matrices at quant 2, which should have given advantage to the high bitrate matrices.

However, I took a look at the screenshot, and they are interesting. On some frames, HVS Best is really impressive, in fact so impressive I wonder if it was a I frame which was used ( on the last 3 ). Could you provide that piece of information.

Also, did you use B frames ?

Edit : for SoulHunter : I also use firefox, and swtiching was possible : just put the mouse cursor over the matrix you want to see, no need to click. As soon as the cursor quit the matrix name, the original is shown.

Soulhunter
20th August 2004, 23:08
Originally posted by Manao

Edit : for Soulhunter : I also use firefox, and switching was possible : just put the mouse cursor over the matrix you want to see, no need to click. As soon as the cursor quit the matrix name, the original is shown.

Thanks for the tip !!!


Bye

SiXXGuNNZ
20th August 2004, 23:31
Originally posted by Manao
At first sight, I would have said it was useless, because you were comparing matrices at quant 2, which should have given advantage to the high bitrate matrices.

However, I took a look at the screenshot, and they are interesting. On some frames, HVS Best is really impressive, in fact so impressive I wonder if it was a I frame which was used ( on the last 3 ). Could you provide that piece of information.

Also, did you use B frames ?

Edit : for SoulHunter : I also use firefox, and swtiching was possible : just put the mouse cursor over the matrix you want to see, no need to click. As soon as the cursor quit the matrix name, the original is shown.

yes, bvop was default xvid settings. I don't know how to check if the frame was an "I"

also, I was gonna do more tests at different bitrates, but grabbing frames from them kinda made me not do it

if there is a script I can use with avisynth that will grab certain frame numbers to bitmap then that would be cool, because opening each avi and saving an image sequence is a pain in the ass

Manao
20th August 2004, 23:53
You should be able to do it with the built in filter called "ImageWriter", using a script like the following : AVISource("c:\foo.avi").trim(n,-1).converttorgb24()
ImageWriter("c:\", 0, 0, "BMP")Where n is the frame you want to save.

If you want to save multiples frame : source = AVISource("c:\foo.avi").converttorgb24()

frames = source.trim(n1,-1) + source.trim(n2,-1) ... + source.trim(nk, -1)

frames.ImageWriter("c:\", 0, k-1, "BMP")Where k is the number of frames to be saved.

To check whether a frame was an I / P / B frame, use FFDshow : in its configuration panel, you can activate the OSD and ask it to show the frame number / frame type / frame mean quantizer.

SiXXGuNNZ
21st August 2004, 00:07
Originally posted by Manao
You should be able to do it with the built in filter called "ImageWriter", using a script like the following : Where n is the frame you want to save.

If you want to save multiples frame : Where k is the number of frames to be saved.

To check whether a frame was an I / P / B frame, use FFDshow : in its configuration panel, you can activate the OSD and ask it to show the frame number / frame type / frame mean quantizer.

thanks for the info, I will check when I get home tonight, I do not have ffdshow installed right now, so I will just do that later when I get home from the bar :)