Method

VipsImagegenerate

Declaration [src] 

int
vips_image_generate (
  VipsImage* image,
  VipsStartFn start_fn,
  VipsGenerateFn generate_fn,
  VipsStopFn stop_fn,
  void* a,
  void* b
)

Description [src]

Generates an image. The action depends on the image type.

For images created with vips_image_new(), vips_image_generate() just attaches the start/generate/stop callbacks and returns.

For images created with vips_image_new_memory(), memory is allocated for the whole image and it is entirely generated using vips_sink_memory().

For images created with vips_image_new_temp_file() and friends, memory for a few scanlines is allocated and vips_sink_disc() used to generate the image in small chunks. As each chunk is generated, it is written to disc.

See also

vips_sink_memory(), vips_image_new(), vips_region_prepare().

Parameters

start_fn

Type: VipsStartFn

Start sequences with this function.

generate_fn

Type: VipsGenerateFn

Generate pixels with this function.

stop_fn

Type: VipsStopFn

Stop sequences with this function.

a

Type: void*

User data.

The argument can be NULL.
The data is owned by the caller of the method.
b

Type: void*

User data.

The argument can be NULL.
The data is owned by the caller of the method.

Return value

Type: int

0 on success, or -1 on error.