ImageWriter

ImageWriter writes frames from a clip as a sequence of image files using the DevIL library (except when you choose the internal "ebmp" format).

Note that frames are not written to the output file until they are actually rendered by this filter.

Syntax and Parameters

ImageWriter (clip, string "file", int "start", int "end", string "type", bool "info")
clip
Source clip; only 8 and 16-bit RGB(A) or greyscale (Y) formats supported.
EBMP type only supports 8-bit RGB, YUV or greyscale (Y) formats.
file
The path + filename prefix of the saved images.
The images will have file names with the pattern: file000000.type, file000001.type, etc.
Sprintf formatting of the filenames is supported.
By default, images will be saved as C:\000000.ebmp, C:\000001.ebmp, etc.

Default: "c:\"

start, end

The start and end of the frame range that will be written. They both default to 0 (where end=0 means last frame). If end is negative, it specifies the number of frames that will be written.

Default: 0, 0

type
Set the filename extension that defines the format of the saved image.
The supported values for type are:

Type

Format

bmp

BMP file format

ebmp

EBMP

dds

DirectDraw Surface

jpg/jpe/jpeg

JPEG

pcx

PiCture eXchange

png

Portable Network Graphics

pbm/pgm/ppm

Portable pixmap

tga

Truevision TGA

tif/tiff

Tag Image File Format

raw

Raw image format

sgi/bw/rgb/rgba

Silicon Graphics Image

Default: "ebmp"

info

When true, overlay progress information on the video clip, showing whether a file is being written, and if so, the filename.

Default: false

Notes

  • JPGs are saved with the quality setting set to 99. For RGB input, the colorspace is converted to YUV with a 4:2:0 chroma subsampling. When the input is greyscale (Y), JPGs are saved in the same Y format.

  • Greyscale BMPs are not written correctly by DevIL (the luma is written to all three channels instead of a single channel). They should be written as ebmp or better yet as PNG or TIFF.

EBMP

The internal image format "ebmp" supports all 8-bit color spaces. The "ebmp" files written from the RGB or Y8 color spaces are standard BMP files, but those produced from YUV spaces are special and can probably only be read by AviSynth's ImageSource. This special format allows you to save and reload raw video in any 8-bit color space.

"EBMP" is an AviSynth extension of the standard Microsoft RIFF image format that allows you to save raw image data.

Examples

Export the entire clip in the current native AviSynth format:

ImageWriter("D:\backup-stills\myvideo")

Write frame 5 to "C:000005.png"

ImageWriter(start=5, end=5, type="png")

Write frame 5 to "000005.png" into the current directory:

ImageWriter("", start=5, end=5, type="png")

Write frames 100 till the end to "F:pic-000100.jpeg", "F:pic-000101.jpeg", etc. and display progress info:

ImageWriter(file="F:\pic-", start=100, type="jpeg", info=true)

Write all frames to "F:00.png", "F:01.png", ..., "F:10.png", "F:11.png", ..., "F:100.png", ... (thus adding zeros filling two digits):

ImageWriter(file="F:\%02d.png")

Load a jpg image and extract the Y (luma) plane and save it as a greyscale png:

FFImageSource("GoldPetals.jpg")
ExtractY()
ImageWriter("GoldPetals-luma", type="png")

Load a YUV420 jpg image and convert it to YUV444 and save it as an ebmp:

FFImageSource("GoldPetals.jpg")
ConvertToYUV444(ChromaInPlacement="MPEG1") # "MPEG2" for YUV422 JPGs
ImageWriter("GoldPetals-YUV444", type="ebmp")

See the ImageReader page for more information on why the JPGs in the last two examples were loaded with FFImageSource instead of the internal ImageReader filter.

Changelog

Version

AviSynth+ r2768

Fix: ImageReader/Writer: path "" means current directory.

AviSynth+ r2502

Fix: ImageWriter crash when no '.' in filename.

AviSynth+ r2487
Added support for support RGB48/64 and Y16 formats.
Fix: flip greyscale except when raw.

AviSynth 2.6.1
DevIL library updated to 1.7.8.
DevIL.dll is now delay loaded, so Avisynth.dll can be used without it, in which case ImageReader/Writer would support only ebmp mode.

AviSynth 2.6.0
ebmp supports all formats; greyscale added for all formats.
Add support for printf formating of filename string, default is ("%06d.%s", n, ext).

AviSynth 2.5.8

Added end=-num_frames (supports negative values as -count for end argument).

AviSynth 2.5.3

Added info parameter.

AviSynth 2.5.2

Added start, end and type parameters.

AviSynth 2.5.1

Added ImageWriter filter in limited form.

$Date: 2022/03/24 12:22:43 $