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-   -   Rendering 16:9 EX1 clips to Mpeg2 (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/115251-rendering-16-9-ex1-clips-mpeg2.html)

Keith Malone February 19th, 2008 07:24 PM

Rendering 16:9 EX1 clips to Mpeg2
 
I have been trying to render EX1 clips (shot at full res HQ, PAL, 25fps) using Vegas 8.0b.

When rendering SD 16:9 footage, I used to use the default PAL DVDA widescreen template and the video would render with the correct aspect ratio.

However, when I render the EX1 clips down to a standard definition MPEG2 file, it plays back with an incorrect aspect ratio. It looks like it is squashed into 4:3.

I think I have tried every combination of setting that involve aspect ratio (via the project properties and the template properties). I have also tried ticking the stretch video to fill output frame size box.

I have also tried to specify 1.777 as the aspect ratio.

I only received my EX1 yesterday so I apologise if I am missing something obvious. Did anyone have a similar issue and how did you resolve it?

thanks in advance,
Keith

Evan Donn February 19th, 2008 08:40 PM

Quote:

Originally Posted by Keith Malone (Post 829253)
However, when I render the EX1 clips down to a standard definition MPEG2 file, it plays back with an incorrect aspect ratio. It looks like it is squashed into 4:3.

Plays where? Widescreen DVDs are anamorphic, so the video is squashed into a 4:3 size, and the DVD player should recognize that and stretch/squash it appropriately based on the display size. My guess is whatever you are playing the clips with isn't recognizing the anamorphic flag and stretching it properly for playback.

Keith Malone February 20th, 2008 03:57 AM

When the rendered clip is played in Windows Media Player it is squashed into a 4:3 size.

When I import the clip into a PAL widescreen DVDA project, it correctly recognises the clip to be in the widescreen format. The only thing now is that it adds the two narrow vertical black bars at both ends of the frame.

Any ideas on how to eliminate this?

David Lorente February 20th, 2008 01:43 PM

The narrow vertical bars are completely normal and must be there. They are part of the horizontal blanking period.

For those who are worried about these, you must know that:
- SD digital video is based on the analog PAL and NTSC standards, so it was designed respecting the timings inherent to each one.
- PAL and NTSC have different active line periods, that is, the period of time of each line who can have image information (the other periods being blanking and sync). For PAL it is 52 μs, and for NTSC it is 52.888 μs (micro-seconds). Total line periods (from one syn pulse to the next) is 64 μs for PAL and 63.555 μs for NTSC.
- As the sampling frequency for both standards is the same (13.5 MHz), having 720 horizontal samples means that a period of 53.333 μs of each line is stored
- Soooooo... instead of sampling just the active line period, a small portion of the blanking period is sampled (just 0.444 μs in NTSC, but 1.333 μs in PAL), and this means you have 9 black pixels at each side of the image. And, even if the image is digitally generated, the analog blanking periods must be respected in order to avoid troubles with displays, etc.

And here's why both sides of the image must be black, and why the black border is thicker for PAL than for NTSC.

Paul Kellett February 20th, 2008 02:01 PM

Keith,i don't get what you get,my EX1 clips,rendered in vegas are properly wide on pc and tv/dvd player,no bars anywhere.I'm rendering something at the moment,i'll have a look tomorrow at vegas templates and dvda and tell you my settings.
In the meantime.tell me your template settings and dvda settings and i'll see if i can help.
Paul

Sami Sanpakkila February 20th, 2008 02:12 PM

Check these two threads from Sony forum and see if they answer your questions

Quote:

Originally Posted by Keith Malone (Post 829434)
When the rendered clip is played in Windows Media Player it is squashed into a 4:3 size.

http://www.sonycreativesoftware.com/...ssageID=574422

Quote:

Originally Posted by Keith Malone (Post 829434)
When I import the clip into a PAL widescreen DVDA project, it correctly recognises the clip to be in the widescreen format. The only thing now is that it adds the two narrow vertical black bars at both ends of the frame.

Any ideas on how to eliminate this?

http://www.sonycreativesoftware.com/...ssageID=573182

Keith Malone February 20th, 2008 04:44 PM

Thanks to all for your replies. Thanks especially to Sami who pointed me to another forum which contained a solution that solved the problem.

So, for anyone else who is stuck: to create a PAL Widescreen DVD (without black vertical pillars at the side) from footage shot on the EX1, do the following:

- set your project properties to HD or HDV as appropriate because this is the correct media aspect.
- render to PAL Widescreen via MPEG2
- ensure that you check:
[X] Stretch video to fill output frame size (do not letterbox).

This works perfectly for me and the file is recognised as widescreen when importing into DVDA.

Don't be put off my the file playing as squashed 4:3 in Windows Media Player. It is obviously not picking up on the widescreen flag. A little annoying, but nonetheless, probably irrelevant in producing a PAL widescreen SD DVD from EX1 footage.

Happy shooting!


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