IBM TJ Watson Research

IBMImagesPngGray

IBMImagesPngGray.mp4

Description

A test using gray scale PNG images. There are four columns of images over a very of white background; the left two columns and right two columns differ only by the Material2D emissiveColor. Each pair of two columns from left to right are
  1. Gray scale PNG
  2. Gray scale PNG with alpha; the outer part is fully transparent and the circular part is partially transparent.

There are two rows of rectangles using these PNG images as textures; the images and rectangles are all 200x200. In the upper row the transparency is set to 0.0F and in the lower row it is set to 0.3F. For columns 1 and 3 (without alpha) the lower image renders differently because the Material2D transparency is used; which is not the case for columns 2 and 4 where the image alpha overrides this. Hence in columns 2 and 4 the upper and lower rendered output is the same. The rendered image color for each pixel is obtained from a gray scale texture by multiplying the emissiveColor by each pixel's intensity; see VRML annotated reference manual "section 4.6.11 Textures" for more information (MPEG-4 being based on VRML for much of it basic function).

To show the rendered output is really derived from emissiveColor a ColorInterpolator is started at t=5s and changes the color of the right hand set of image shapes repeatedly over a 10s period.

Screenshot

Snapshot of rendered output.



Snapshot taken during interpolation of colors.



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