Log in

View Full Version : DVB-T (Freeview) upscaling to 720p


MegatronUK
28th June 2007, 19:44
Does anyone else do much upscaling of recordings from the UK Freeview service? I mostly stick to encoding standard 720x576 xvid avi's at about 650-700mb per hour... but on the odd occaision I'll try scaling up a movie.

I've had a few goes and it started off a bit hit and miss, but have managed to get some good results.

The best one I've done so far was I Robot, which was broadcast on Channel 4 a couple of months ago.

My process is:

1. Get recordings onto PC using TwinRip to extract PVA files from my Pace Twin PVR.
2. Edit out adverts using Cuttermaran
3. Encode video + audio in AVI container using Avidemux at the following settings:
Xvid MPEG4
- 2-pass final size or alternatively 4600kbit or higher 1-pass CBR.
- Chroma and Interlacing modes turned on
- HQ B frames
- Level 6 motion detection
- Level 4 extended search
- MPEG & Trellis quantisation
- Filter: MPlayer resize (720x576 to 1280x720, Lanczos3)
- Filter: MPlayer hqdn3d denoise filter (default values)
- Filter: MSharpen (Strength 120 to 150)
- I dont apply any de-interlacing

Audio is almost always left as the default MPEG2 48KHz stereo format as broadcast - there seems to be little to be saved when transcoding it to MP3.

I watch all of this on a 720p LCD TV (cheap 27" Mirai model in my bedroom) via a Deuple 350 HD media player.

Here's an example of the output
http://www.target-earth.net/downloads/vlcsnap-918352.jpg

BBC1, BBC2 and Channel 4 seem to be the best for getting high quality transmissions that are suitable for upscaling.

The only downside I've found is that my dual Athlon MP 2600 setup is getting a little long in the tooth to be doing this! :)

Anyone else bother upscaling any Freeview content? What are your methods?

SeeMoreDigital
28th June 2007, 20:08
Interesting....

Are you able to supply us with some short samples of your original 720x576 MPEG-2 source and your 1280x720 MPEG-4 encode?

You can use MyTempDir (http://www.mytempdir.com/) to host them...


Cheers

MegatronUK
28th June 2007, 20:29
Sorry, the original is long gone... but I'm uploading a 1m 45s extract from the upscaled version now.

MegatronUK
28th June 2007, 20:51
Ok, two examples:

I Robot, 1280x720, 25fps, 192kbit MPEG-2 audio, XVID
Originally aired on Channel 4
Full movie size 3,086,274Kb
Clip length 40,892Kb (1m 23s)
http://www.mytempdir.com/1364689

Enemy at the Gates, 1280x720, 25fps, 256kbit MPEG-2 audio, XVID
Originally aired on BBC1
Full movie size 2,665,849Kb
Clip length 16,673Kb (42s)
http://www.mytempdir.com/1364692