Vix.Vips.Image (vix v0.2.1) View Source
Vips Image
Link to this section Summary
Functions
Get bands
Get filename
Get all image header field names.
Get image header value.
Get image header value as string.
Get height
Get mode
Get n_pages
Opens path
for reading, returns an instance of Vix.Vips.Image.t/0
Make a VipsImage from list.
Make a VipsImage which, when written to, will create a temporary file on disc.
Get offset
Get orientation
Get page_height
Get scale
Get width
Write vips_image
to a file.
Get xoffset
Get xres
Get yoffset
Get yres
Link to this section Types
Specs
t()
Represents an instance of libvips image
Link to this section Functions
Specs
bands(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get bands
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-bands
Specs
filename(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get filename
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-filename
Specs
header_field_names(Vix.Vips.Image.t()) :: {:ok, [String.t()]} | {:error, term()}
Get all image header field names.
See https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-fields for more details
Specs
header_value(Vix.Vips.Image.t(), String.t()) :: {:ok, integer() | float() | String.t() | [integer()]} | {:error, term()}
Get image header value.
This is a generic function to get header value.
Casts the value to appropriate type. Currently it only supports values of type integer, float, string and list of integer values. Use Vix.Vips.Image.header_value_as_string/2
to get string representation of any header value.
{:ok, width} = Image.header_value(vips_image, "width")
Specs
header_value_as_string(Vix.Vips.Image.t(), String.t()) :: {:ok, String.t()} | {:error, term()}
Get image header value as string.
This is generic method to get string representation of a header value. If value is VipsBlob, then it returns base64 encoded data.
See: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-as-string
Specs
height(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get height
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-height
Specs
mode(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get mode
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-mode
Specs
n_pages(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get n_pages
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-n-pages
Specs
new_from_file(String.t()) :: {:ok, Vix.Vips.Image.t()} | {:error, term()}
Opens path
for reading, returns an instance of Vix.Vips.Image.t/0
It can load files in many image formats, including VIPS, TIFF, PNG, JPEG, FITS, Matlab, OpenEXR, CSV, WebP, Radiance, RAW, PPM and others.
Load options may be appended to filename as "[name=value,...]". For example:
Image.new_from_file("fred.jpg[shrink=2]")
Will open "fred.jpg", downsampling by a factor of two.
The full set of options available depend upon the load operation that will be executed. Try something like:
$ vips jpegload
at the command-line to see a summary of the available options for the JPEG loader.
Loading is fast: only enough of the image is loaded to be able to fill out the header. Pixels will only be decompressed when they are needed.
Specs
Make a VipsImage from list.
This convenience function makes an image which is a matrix: a one-band VIPS_FORMAT_DOUBLE image held in memory. Useful for vips operations such as conv
.
mask = Image.new_matrix_from_array(3, 3, [[0, 1, 0], [1, 1, 1], [0, 1, 0]])
Optional
- scale - Default: 1
- offset - Default: 0
Specs
Make a VipsImage which, when written to, will create a temporary file on disc.
The file will be automatically deleted when the image is destroyed. format is something like "%s.v"
for a vips file.
The file is created in the temporary directory. This is set with the environment variable TMPDIR. If this is not set, then on Unix systems, vips will default to /tmp
. On Windows, vips uses GetTempPath()
to find the temporary directory.
vips_image = Image.new_temp_file("%s.v")
Specs
offset(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get offset
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-offset
Specs
orientation(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get orientation
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-orientation
Specs
page_height(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get page_height
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-page-height
Specs
scale(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get scale
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-scale
Specs
width(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get width
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-width
Specs
write_to_file(Vix.Vips.Image.t(), String.t()) :: :ok | {:error, term()}
Write vips_image
to a file.
Save options may be encoded in the filename or given as a hash. For example:
Image.write_to_file(vips_image, "fred.jpg[Q=90]")
A saver is selected based on path
. The full set of save options depend on the selected saver. Try something like:
$ vips jpegsave
at the command-line to see all the available options for JPEG save.
Specs
xoffset(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get xoffset
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-xoffset
Specs
xres(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get xres
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-xres
Specs
yoffset(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get yoffset
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-yoffset
Specs
yres(Vix.Vips.Image.t()) :: {:ok, term()} | {:error, term()}
Get yres
see: https://libvips.github.io/libvips/API/current/libvips-header.html#vips-image-get-yres