Method Image.GIF._render_block()

Method _render_block

string _render_block(int x, int y, int xsize, int ysize, int bpp, string indices, zero|string colortable, int interlace)

Description

Advanced (!) method for writing renderblocks for placement in a GIF file. This method only applies LZW encoding on the indices and makes the correct headers.

Parameter x

Parameter y

Position of this image.

Parameter xsize

Parameter ysize

Size of the image. Length if the indices string must be xsize*ysize.

Parameter bpp

Bits per pixels in the indices. Valid range 1..8.

Parameter indices

The image indices as an 8bit indices.

Parameter colortable

Colortable with colors to write as palette. If this argument is zero, no local colortable is written. Colortable string len must be 1<<bpp.

Parameter interlace

Interlace index data and set interlace bit. The given string should _not_ be pre-interlaced.

Note

This is in the very advanced sector of the GIF support; please read about how GIF files works.

See also

encode, _encode, header_block, end_block