blocky party footage from HDV codec,rolling shutter or other? at DVinfo.net

Robert Koster · September 11th, 2008, 04:20 AM

I've had my V1 for about a year and shoot alot on it. When filming a recent series of dance parties and later viewing the captured footage in premiere, alot of the images were blocky as if the tape head were dirty (though their not). So Can HDV not handle the combination of stage lights and smoke machines, strobes, etc.... the footage looked just terrible-thought I was capturing off an old VHS tape. Or could it be the codec I am capturing with in Premiere? I couldnt see it when viewing the footage off the Camera LCD.Is this just the reality of MPEG2 codec? Any ideas?

Leslie Wand · September 11th, 2008, 04:50 AM

if you're not seeing it in playback on the camera then the fault lies with the capyure / codec.

which vers prem?

leslie

K.C. Luke · September 11th, 2008, 05:14 AM

Can attach some sample jpg? or you may take a look CMOS Rolling Shutter

http://www.dvinfo.net/conf/sony-hvr-...s-flashes.html

Stephan Stryhanyn · September 11th, 2008, 05:44 AM

Probably pixellization / bandwidth starvation of the MPEG2 encoder due to the strobe lights (as mentioned in the thread pointed to by K.C. Luke), which I too have observed with flash photography. The MPEG2 blocks are small in HDV, which might explain why you didn't see them on the LCD.

Robert Koster · September 11th, 2008, 06:01 AM

I am using Premiere CS3... and have since downloaded the 3.1.1 update as i was getting red frames.
I will try to upload a screen capture. Do you think this could be eliminated if I used an intermediate codec like cineform. I had read on this forum of a similar problem someone had... and it was explained that the color format of HDV (4:2:1) is to blame for this.. Whereas cineform can convert the color into 4:2:2. Has anyone had experience with this.

Stephan Stryhanyn · September 11th, 2008, 03:20 PM

"Do you think this could be eliminated if I used an intermediate codec like cineform":
- If you have blocks all over the picture, like periodically with the strobe lights (bandwidth starvation): no.
- If you have blocks staying continuously, only on the saturated red parts of the picture (4:2:0 chroma subsampling): would most probably improve a lot, but better check with the free trial before committing.

Best to post a frame grab to avoid overtheorizing.

September 11th, 2008, 04:20 AM	#1
Robert Koster New Boot Join Date: Jul 2005 Location: Bali, Indonesia Posts: 5	blocky party footage from HDV codec,rolling shutter or other? I've had my V1 for about a year and shoot alot on it. When filming a recent series of dance parties and later viewing the captured footage in premiere, alot of the images were blocky as if the tape head were dirty (though their not). So Can HDV not handle the combination of stage lights and smoke machines, strobes, etc.... the footage looked just terrible-thought I was capturing off an old VHS tape. Or could it be the codec I am capturing with in Premiere? I couldnt see it when viewing the footage off the Camera LCD.Is this just the reality of MPEG2 codec? Any ideas?

September 11th, 2008, 05:14 AM	#3
K.C. Luke Regular Crew Join Date: Jul 2007 Location: Singapore Posts: 173	Can attach some sample jpg? or you may take a look CMOS Rolling Shutter http://www.dvinfo.net/conf/sony-hvr-...s-flashes.html __________________ Edit on Adobe Creative Suite Production Premium CS5 Mac 64BIT

September 11th, 2008, 06:01 AM	#5
Robert Koster New Boot Join Date: Jul 2005 Location: Bali, Indonesia Posts: 5	Block party I am using Premiere CS3... and have since downloaded the 3.1.1 update as i was getting red frames. I will try to upload a screen capture. Do you think this could be eliminated if I used an intermediate codec like cineform. I had read on this forum of a similar problem someone had... and it was explained that the color format of HDV (4:2:1) is to blame for this.. Whereas cineform can convert the color into 4:2:2. Has anyone had experience with this. Last edited by Robert Koster; September 11th, 2008 at 07:00 AM.

September 11th, 2008, 04:50 AM	#2
Leslie Wand Trustee Join Date: Mar 2004 Location: upper hunter, australia Posts: 1,410	if you're not seeing it in playback on the camera then the fault lies with the capyure / codec. which vers prem? leslie

September 11th, 2008, 05:44 AM	#4
Stephan Stryhanyn Regular Crew Join Date: Dec 2006 Location: France Posts: 48	Probably pixellization / bandwidth starvation of the MPEG2 encoder due to the strobe lights (as mentioned in the thread pointed to by K.C. Luke), which I too have observed with flash photography. The MPEG2 blocks are small in HDV, which might explain why you didn't see them on the LCD.

September 11th, 2008, 03:20 PM	#6
Stephan Stryhanyn Regular Crew Join Date: Dec 2006 Location: France Posts: 48	"Do you think this could be eliminated if I used an intermediate codec like cineform": - If you have blocks all over the picture, like periodically with the strobe lights (bandwidth starvation): no. - If you have blocks staying continuously, only on the saturated red parts of the picture (4:2:0 chroma subsampling): would most probably improve a lot, but better check with the free trial before committing. Best to post a frame grab to avoid overtheorizing.