ImageMagick: Command-line Tools: Stream

Stream is a lightweight tool to stream one or more pixel components of the image or portion of the image to your choice of storage formats. It writes the pixel components as they are read from the input image a row at a time making stream desirable when working with large images or when you require raw pixel components.

Example Usage

We list a few examples of the stream command here to illustrate its usefulness and ease of use. To get started, lets stream the red, green, blue components of a 640x480 JPEG image to disk as unsigned characters:

  stream -map rgb -storage-type char image.jpg pixels.dat
  display -depth 8 -size 640x480 rgb:pixels.dat

Here we extract a 100x100 region from a TIFF image in the grayscale format as doubles:

  stream -map i -storage-type double -extract 100x100+30+40 image.tif gray.raw

You can also associate the region to extract with the image filename:

  stream -map i -storage-type double 'image.tif[100x100+30+40]' gray.raw

Option Summary

The stream command recognizes these options. Click on an option to get more details about how that option works.

Option	Description
-authenticate value	decrypt image with this password
-channel type	apply option to select image channels
-colorspace type	set image colorspace
-debug events	display copious debugging information
-define format:option	define one or more image format options
-density geometry	horizontal and vertical density of the image
-depth value	image depth
-extract geometry	extract area from image
-help	print program options
-interlace type	type of image interlacing scheme
-interpolate method	pixel color interpolation method
-limit type value	pixel cache resource limit
-list type	Color, Configure, Delegate, Format, Magic, Module, Resource, or Type
-log format	format of debugging information
-map components	store pixels in this format.
-monitor	monitor progress
-quantize colorspace	reduce image colors in this colorspace
-quiet	suppress all warning messages
-regard-warnings	pay attention to warning messages.
-respect-parenthesis	settings remain in effect until parenthesis boundary.
-sampling-factor geometry	horizontal and vertical sampling factor
-seed value	seed a new sequence of pseudo-random numbers
-set attribute value	set an image attribute
-size geometry	width and height of image
-storage-type type	store pixels with this storage type.
-transparent-color color	transparent color
-verbose	print detailed information about the image
-version	print version information
-virtual-pixel method	access method for pixels outside the boundaries of the image