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Creating MPEGs with IDL 6.2

IDL provides an IDLgrMPEG class that allows the user to save an array of image frames as an MPEG movie. See the IDL Reference guide.

The MPEG_PUT procedure stores the specified image array at a specified frame index in an MPEG sequence. The MPEG_SAVE procedure encodes and saves an open MPEG sequence. The images can be read using the READ_IMAGE function.

Two examples of IDL modules to produce movies are given below. Example1 is a command line MPEG generator and Example2 provides a user interface for the parameters.

Example1 - Command line MPEG generator

make_mpg, synopsis

This module, mpg.pro reads a sequence of images (named prefix00001.suffix) and produces an MPEG1 or MPEG2 movie. Supported formats are: BMP, GIF, JPEG, PNG, PPM, SRF, TIFF, DICOM

Parameters

prefix string(required) A string specifying the prefix of the images to read included the path, for example "/home/data/images/Image"
suffix string(required) A string specifying the suffix of the images to read, for example "jpg".
n_start integer(required) An integer specifying the first image in the sequence.
n_end integer(required) An integer specifying the last image in the sequence.
digits integer(required) An integer specifying the number of digits of the number field in the sequence, for example image00001.jpg would require digits=5.
dims integer(optional) An integer array specifying the size of the output image. If not specified the size of the first image is used.
format integer(optional) An integer with values 0 for MPEG1 and 1 for MPEG2. Default is MPEG1.
frame_rate integer(optional) An integer with values.
1 = 23.976 frames/sec: NTSC encapsulated film rate.
2 = 24 frames/sec: standard film rate.
3 = 25 frames/sec: PAL video frame rate
4 = 29.97 frames/sec: NTSC video frame rate
5 = 30 frames/sec: NTSC drop frame video rate (the default).
6 = 50 frames/sec: double frame rate/progressive PAL
7 = 59.94 frames/sec: double frame rate NTSC
8 = 60 frames/sec: double frame rate NTSC
mpeg_file string(optional) A string specifying the output MPEG file (default outfile.mpg)
tmp_dir string(optional) A string specifying temporary directory to use for the temporary image files.

To run the IDL movie generator type in a shell:

    %module load idl
    %idl
    > .compile mpg.pro
    > make_mpg, prefix='image', suffix='.bmp', n_start=0, n_end=100, digits=5, dims=[512,512], mpeg_file='mympeg.mpg'

Example2 - MPEG generator with a GUI

xmpeg, synopsis

This IDL project, mpg_gen.tar.gz reads a sequence of images (named prefix00001.suffix) and produces an MPEG1 or MPEG2 movie. Supported input image formats are: BMP, GIF, JPEG, PNG, PPM, SRF, TIFF, DICOM. A GUI is provided to enter the parameters.

Parameters

prefix string(required) A string specifying the prefix of the images to read included the path, for example "/home/data/images/Image".
suffix string(required) A string specifying the suffix of the images to read, for example "jpg".
n_start integer(required) An integer specifying the first image in the sequence.
n_end integer(required) An integer specifying the last image in the sequence.
digits integer(required) An integer specifying the number of digits of the number field in the sequence, for example image00001.jpg would require digits=5.
xsize integer(optional) An integer specifying the x size of the output image. If not specified the size of the first image is used.
ysize integer(optional) An integer specifying the y size of the output image. If not specified the size of the first image is used.
format integer(optional) An integer with values 0 for MPEG1 and 1 for MPEG2. Default is MPEG1.
frame_rate integer(optional) An integer with values.
1 = 23.976 frames/sec: NTSC encapsulated film rate.
2 = 24 frames/sec: standard film rate.
3 = 25 frames/sec: PAL video frame rate
4 = 29.97 frames/sec: NTSC video frame rate
5 = 30 frames/sec: NTSC drop frame video rate (the default).
6 = 50 frames/sec: double frame rate/progressive PAL.
7 = 59.94 frames/sec: double frame rate NTSC.
8 = 60 frames/sec: double frame rate NTSC
mpeg_file string(optional) A string specifying the output MPEG file (default outfile.mpg).
tmp_dir string(optional) A string specifying temporary directory to use for the temporary image files.

After unzipping and untaring the files please refer to the README file for running the project.