HELP! Taking HD videos from the iPad's screen to SD DVD

[aliagha77]

Good info...thank you.....what if we used the video in areas where there's motion, and where ever there is a still shot with text, we substitute a graphic image instead of the video feed? Will that give us better rendition of the actual text since its just a graphic?

Im thinking we'll have to do more zooming in to areas to get better clarity.

So one question...if we use the background image...that should definitely be set to 853 x 480 to take up the full width on a 16:9 hdtv?

Also there shouldn't be any difference recording off the ipad 2 / 3 should there since we cant really take advantage of the new ones higher resolution?

[aliagha77]

And yes in that image the text seemed pretty clear...if the "video area" that we have allocated within the background image is about 300x400 for example...we would need to make sure we have it set to square pixels, and par corrected to get that effect? I'll just double check that with him...

[poisondeathray]

Good info...thank you.....what if we used the video in areas where there's motion, and where ever there is a still shot with text, we substitute a graphic image instead of the video feed? Will that give us better rendition of the actual text since its just a graphic?

graphics / RGB images never look as crisp or as sharp when placed on DVD (Even if there is no scaling)

Some reasons are

1) chroma subsampling - MPEG2 uses YV12 or 4:2:0 subsampling. This means for every 4 luminance pixels only 1 stores color. The 720x480 image would only have 360x240 of color information . So especially colored text edges will either look blurry or blocky & pixellated depending on the chroma upsampling that the display does. Eitherway, it won't look sharp as an RGB image (RGB color is unsubsampled - it's "full")

2) MPEG2 compression - DVD's are highly compressed, compression artifacts

Similarly when you record at 1440x1080 (4:3 square pixel), the AVC is YV12 (4:2:0 subsampled), so the 1440x1080 only has a maximum theoretical color resolution of 720x540 . Further, the AVC is also compressed

When you insert graphics (e.g. screen replacement) into live action footage. There are a lot of compositing "gotchas" . Often it looks fake if you don't do it right, because the motion blur doesn't match the blur that the rest of the live action footage has (primarily due to the shutter speed at which you shot the live action) . Things like reflections, glares don't look right unless you do it properly. It's not as simple as just swapping a layer out - your FX guy should know all this

Im thinking we'll have to do more zooming in to areas to get better clarity.

I think so... that's what I've been trying suggest all along. You can still use the background as an intro/ establishing shot. Just when you get to the important parts I think it's vital to show clear text (especially since this is a text/graphic display app) . You're not promoting ipad's, your promoting the application for the ipad correct? It's crucially important to show your app in the best light possible

So one question...if we use the background image...that should definitely be set to 853 x 480 to take up the full width on a 16:9 hdtv?

Yes, the square pixel equivalent is rounded to 854x480 . That is resized to 720x480 for NTSC DVD, and the AR flag is set to 16:9 . All common software for these tasks (e.g. photoshop, AE, editors) have PAR correction . You have to know if you're working in square pixels, or not - otherwise things get distorted

Also there shouldn't be any difference recording off the ipad 2 / 3 should there since we cant really take advantage of the new ones higher resolution?

There are more advantages to recording higher resolution even if delivering at a lower resolution . Recall earlier I mentioned reframing - this allows you more leeway in reframing and zooming in. You're able to do more manipulations. Also because of oversampling, you have more advantages in overall quality, less noise .
http://en.wikipedia.org/wiki/Oversampling

[poisondeathray]

And yes in that image the text seemed pretty clear...if the "video area" that we have allocated within the background image is about 300x400 for example...we would need to make sure we have it set to square pixels, and par corrected to get that effect? I'll just double check that with him...

All the common video software has "PAR correction" . So if you're working in a 720x480 timeline, you can toggle a switch to see what it would look like at 16:9 for example

Another way to do it is to use square pixels all the way, then convert it to non square pixels

e.g. you would use 854x480 all the way for 16:9 (this way everything looks right, all your images, backgrounds, videos, assets), and at the final step convert to DVD (it's "squished" to 720x480 with 16:9 AR) . More common would be to use an 16:9 HD timeline 1280x720 or 1920x1080 - this way you can simultaneously make a blu-ray or DVD, or something for youtube/vimeo without redoing the whole project. You save yourself a lot of time and can promote in other avenues like web. By restricting yourself to DVD and SD, you're limiting your potential audience and shooting yourself in the foot (IMO) . In today's day and age, everything is HD. You can't buy a SD TV anymore. Even elemtenary school kids shoot in HD and share videos on youtube

[poisondeathray]

Poison, the demo's on dvd will be used at convention shows to pass out to people.

DVD will still be around for a long time...

But another thing that people pass out at conventions is usb sticks with HD video . usb sticks are cheap cost/GB . HD can look great . SD.. not so much

[aliagha77]

So for example....if we were to create a "video" but just have a STILL image of the home screen inside the ipad frame (with all the apps and names under it), will it display that text more clear than the same footage which actually comes from a video feed on dvd?

[poisondeathray]

So for example....if we were to create a "video" but just have a STILL image of the home screen inside the ipad frame (with all the apps and names under it), will it display that text more clear than the same footage which actually comes from a video feed on dvd?

If you mean the video is DVD, but the screen replacement source is an RGB image instead of the YV12 screen capture from the ipad, the answer is marginally. You won't notice much of a difference - the limiting "bottleneck" is still DVD. (low resolution, color sampling, compression are still the problems)

[aliagha77]

So would it look any worse than a photo album thats on a dvd?

[poisondeathray]

So would it look any worse than a photo album thats on a dvd?

Do you mean like a DVD slide show ? or a DVD with jpeg still images in a folder (as a data disc) ? These are different things

A DVD slideshow is encoded as MPEG2 (so it has the same sampling issues, compression issues, resolution issues).

DVD (regardless) only outputs a 720x480 signal (in NTSC land).

But even if you had a DVD player than can read 4k jpg still images from a folder , the signal it outputs is still 720x480 to the TV. The critical factor is still low resolution.