Freelancer
16th July 2003, 04:22
Hello
I've been recording The Simpsons via my DVB-S card. There are certain anomalies present as far as the image is concerned and I'm trying to fix this (note: this is not card related or anything, everything else I record is OK. It's only this particular station / show). I've done extensive testing for about two weeks now but in the end I'm still stuck.
First some source info:
PAL 25 FPS
720×576
MPEG-2, average bitrate 5mbps
Now I don't know how many times this has been edited or transcoded before it was transmitted or what the original sorce was but something must have been done with it.
At first I was dealing with season 13. The artifacts (I will get to that!) were only present during intro and outro. OK so I thought: Maybe the intro and outro scenes are just modified from the older seasons. Since it wasn't so bad I decided to ignore this.
BUT now I'm dealing with season 6 and since it's older the anomalies are present all the time.
The anomalies: (see pictures below)
1) some sort of a temporal effect (delay / displacement?). This has only appeared in older seasons and on rare ocasions during the intro/outro in newer seasons. It's a real pain in the a$$!
2) weird or pretty much normal interlace (older seasons have somewhat normal, newer have weird; this can be fixed by deinterlacing)
3) dot crawl (ONLY during credits, most visible on horizontal lines and letters). This basically looks like interlace on the wrong axis. I can tolerate this since I don't care about intro / outro.
Now let me serve you some pictures (this is my source, no editing has been applied):
Season 6
dot crawl (http://freeweb.siol.net/cehovin4/images/simpsons/S06_dotcrawl.jpg)
temporal+interlace (http://freeweb.siol.net/cehovin4/images/simpsons/S06_temporal+interlace.jpg)
Season 13
dot crawl (http://freeweb.siol.net/cehovin4/images/simpsons/S13_dotcrawl.jpg)
something that might look like interlace. Note: this one is a 450KB BMP. If I use compression the effect pretty much dissapears :(. (http://freeweb.siol.net/cehovin4/images/simpsons/S13_interlace.bmp)
same thing sample #2 (http://freeweb.siol.net/cehovin4/images/simpsons/S13_interlace2.jpg)
I've never seen that strange/messed up interlace before or that temporal effect. I think this is the result of editing the original source to fit whatever specifications were necessary to transmit the thing. Basically I don't even know what to think anymore. All I know is that these problems are out of my league. I hope you guys can shed some light on these annoyances. I'd appreciate any feedback.
Regards,
Freelancer
I've been recording The Simpsons via my DVB-S card. There are certain anomalies present as far as the image is concerned and I'm trying to fix this (note: this is not card related or anything, everything else I record is OK. It's only this particular station / show). I've done extensive testing for about two weeks now but in the end I'm still stuck.
First some source info:
PAL 25 FPS
720×576
MPEG-2, average bitrate 5mbps
Now I don't know how many times this has been edited or transcoded before it was transmitted or what the original sorce was but something must have been done with it.
At first I was dealing with season 13. The artifacts (I will get to that!) were only present during intro and outro. OK so I thought: Maybe the intro and outro scenes are just modified from the older seasons. Since it wasn't so bad I decided to ignore this.
BUT now I'm dealing with season 6 and since it's older the anomalies are present all the time.
The anomalies: (see pictures below)
1) some sort of a temporal effect (delay / displacement?). This has only appeared in older seasons and on rare ocasions during the intro/outro in newer seasons. It's a real pain in the a$$!
2) weird or pretty much normal interlace (older seasons have somewhat normal, newer have weird; this can be fixed by deinterlacing)
3) dot crawl (ONLY during credits, most visible on horizontal lines and letters). This basically looks like interlace on the wrong axis. I can tolerate this since I don't care about intro / outro.
Now let me serve you some pictures (this is my source, no editing has been applied):
Season 6
dot crawl (http://freeweb.siol.net/cehovin4/images/simpsons/S06_dotcrawl.jpg)
temporal+interlace (http://freeweb.siol.net/cehovin4/images/simpsons/S06_temporal+interlace.jpg)
Season 13
dot crawl (http://freeweb.siol.net/cehovin4/images/simpsons/S13_dotcrawl.jpg)
something that might look like interlace. Note: this one is a 450KB BMP. If I use compression the effect pretty much dissapears :(. (http://freeweb.siol.net/cehovin4/images/simpsons/S13_interlace.bmp)
same thing sample #2 (http://freeweb.siol.net/cehovin4/images/simpsons/S13_interlace2.jpg)
I've never seen that strange/messed up interlace before or that temporal effect. I think this is the result of editing the original source to fit whatever specifications were necessary to transmit the thing. Basically I don't even know what to think anymore. All I know is that these problems are out of my league. I hope you guys can shed some light on these annoyances. I'd appreciate any feedback.
Regards,
Freelancer