De-interlacing video using MotionWavelets single-field capture mode.

First let’s look at the problems encountered when digitizing interlaced video at 640x480 resolution.

Most common video sources, such as video cameras, VCRs and TV tuners, output a standard NTSC video signal. This signal is interlaced, which means that each video frame is composed of two interleaved fields. One field consists of the even-numbered rows, the other field is made up of the odd-numbered rows. The two fields of each frame are not intended to be viewed at the same time, because they were not captured at the same time – odd and even fields were captured alternately every 1/60th of a second. On a standard television, these fields are displayed alternately – each for 1/60th of a second – so the moving image appears correct.

However, when an interlaced video signal is digitized to 640x480 and played on a computer display, the odd and even fields are displayed at the same time - each pair for 1/30 of a second. Artifacts are visible in the video because fields captured at different times are being played back at the same time. These artifacts are called interlace artifacts.

The single-field capture mode of MotionWavelets was designed to eliminate interlace artifacts. The images below demonstrate the big improvement in image quality that de-interlacing can provide. The first image is a frame taken from a 640x480 video clip that was captured without de-interlacing (the frame has been reduced in size to 320x240 for viewing convenience). The second image shows what the same frame from the same video clip looks like when de-interlacing is enabled using MotionWavelets’ single-field capture mode.

640x480 video captured without de-interlacing

640x480 video de-interlaced using MotionWavelets’ single-field capture mode

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