When do i need to deinterlace

MetaFox 2. DownZemAll 2. TS-Doctor 3. FFmpeg Batch Converte MKVToolNix Kid3 3. Recent DVD Hacks. Sony BDP-S Panasonic DVD-S Philips BDP Samsung BD-H LG BP Pioneer DV There are a few but important cases when deinterlacing can give you unsatisfactory results.

TV channels can air a music video clip interlaced and the next one non-interlaced. The same applies to commercials: One commercial is 25fps, the next one is 50fps. TV channels can air the news interlaced, but the intro to the news spinning globes etc is not interlaced. The professional coverage of the 11th September attacks by the Saudi Arabian terrorists on the World Trade Center is aired progressively but the amateur footage of the events is aired 50fps.

Vice versa a coverage may be 50fps, but changes to 25fps when old footage e. World War 2 films with Hitler is shown. A program may be 25fps, but the ending credits are 50fps. A program may be 25fps, but a change from one scene to another may be interlaced see below.

A single frame can even consist of progressive parts and interlaced parts see below. Some channels air x which is always non-interlaced because heights below pixels cannot be interlaced as defined by international committees. Thus this can give you some problems if you deinterlace everything automatically or leave everything progressive. As you can see it's interlaced and has to be deinterlaced. The same music clip, the same scene, but different TV channel Belgium channel 'Zik.

Not interlaced, thus doesn't need to be deinterlaced. You'd lose quality if you deinterlaced it, though the quality loss wouldn't be high see below , because the deinterlacing methods described on this site are quite good. Side note: The next video music clip after this one, was interlaced again.

Quality loss after unnecessarily deinterlacing of progressive frames: Capture from a commercial for the new Volkswagen Phaeton. Magnified original non-interlaced The unnecessarily deinterlaced version.

As you can see only the moving part the high diver shows greater quality loss. Other details are nearly the same. Compare the eyelash. Some of the fine lines have stairs in them. Virtualdub's Deinterlacing method "Duplicate". Compare the fine hairs top and bottom and the letters.

Virtualdub's Deinterlacing method "Discard" followed by "Bicubic Resize". Compare the hairs and letters. Deinterlacing by blending: This is Deinterlacing by blending. Not only that a progressive frame can be motion blurred look at Jamiroquai's left hand in the second picture above , now you also blend the next field into this one.

So you really get a blurry result. However, the final result sometimes is not as bad as you might think. Take this example of a music clip: It was resized down to x and thus hasn't got any interlacing artefacts mice teeth.

It looks quite good because the original was filmed with 24fps 35mm , thus had a lot of motion blur in it anyway. The lady you see here is the English year-old Chloe Bruce that's her real name. She has won countless world championships. Go Chloe, kick away bad artifacts 15 sec, 1. This is a commercial for the product "Veet", a leg hair removal spray they call it "mousse" , that needs only 8 minutes after application to remove your leg hair so they say in this commercial.

To make it even more polishing, here's the Polish non-interlaced version 9. No interlacing artefacts, no deinterlacing artefacts.

Pure Polish Progressive Pleasure. Pretty neat. From the Polish channel Viva Polska. Look at the above commercial for "Garnier Fructis, Color Resist" click the pictures to zoom. The first scene is progressive. You won't see any interlacing mice teeth of the movement of the water drops.

Reply to this Discussion! Login or Sign Up. I matched my sequence settings to this. My question is do I need to de-interlace my VX footage before editing? If so, what is the best method? Any help is greatly appreciated. Well, where will this be seen? However, if on the web, then you need to deinterlace.

Display each half-picture like a full picture, by simply displaying each line twice. Preserves temporal resolution of interlaced video. Only display one of the half-pictures, discard the other.

Other name: "single field". Both temporal and vertical spatial resolutions are halved. Can be used for slower computers or to give interlaced video movie-like look with characteristic judder. Bob with linear interpolation: instead of displaying each line twice, line 2 is created as the average of line 1 and 3, etc. Blender half resolution. Display a half-picture that is created as the average of the two original half-pictures.

Generates a full picture taking the odd lines from the odd half-picture, and creating the even lines through a complicated algorithm involving ME, MC, edge-oriented interpolation that uses information from both half-pictures.

Generates a full picture taking the odd lines from the odd half-picture, and creating the even lines through a complicated algorithm that includes both temporal and spatial interpolation. Bob with Yadif interpolation. Caution : Very heavy on the CPU. The latest two half-pictures are displayed, the old one fading out. Inverse telecine. Removes telecine from NTSC telecined video in realtime, losslessly recovering the progressive signal. Note : Only applicable to telecined sources.

For true interlaced sources, use a doubler. Which one is a matter of taste. Try Linear first; it is pretty good while simple and light on the CPU. This table summarizes various technical information on the algorithms. Don't be afraid to dive in - it's intended for users. If you are a developer looking for more detailed technical understanding, this module also has a section in the Hacker Guide. Note that the picture will be scaled before being displayed, so the number of lines just tells us how detailed the picture could potentially be.

The luma Y component scale I "analog", J full scale, "digital", Line 1 of output is the mean of lines 1 and 2 in input, line 2 of output is the mean of lines 3 and 4 in input, and so on. The first line of output is copied from the first line of input. For any other output line N, the line is the mean of input lines N and N That is, the second line of output is the mean of lines 1 and 2 in input, the third line is the mean of lines 2 and 3, The sliding averaging procedure preserves the original vertical resolution.

The same goes for Linear and Yadif 2x , though it's a bit smarter about the process. Though, it can also change frame rate on special effects such as the Psychedelic effect if filter is turned on.

Still, even the basic Bob is slightly more clever than just a 2x version of Discard.