Legacy ImageMagick Discussions Archive

Hi everyone,

I've just started to look at ImageMagick (or actually Magick++) so I apologize for any stupid questions...

I have a multipage TIFF image and need to count how many of the pages are colored and how many are grayscale (from a C++ program). My first thought was to get the number of total pages (don't know how yet) and then retrieve each page using the read("myfile.tiff[n]") syntax. For each page retrieved I call getConstPixels() and then iterate over all the pixels and compare the R, G and B values for each pixel with opacity != TransparentOpacity. If they're not equal the page contains color and I move on to the next page.

Is this the way to go or is there a better (talking performance) approach?

Btw, how do I get the total number of pages? I know how to do it from the command line (identify -format %n myfile.tiff), but what is the C++ equivalent?

/ Mikael

To get the number of images with Magick++ use a list which can return its length. To get you started:

list<Image> imageList;
readImages( &imageList, "image.tiff" );

To determine of the image is grayscale you could use statistics() and compare the red, green, and blue channels. If they are equal, the image is gray.

A list seems like a good start

And I'll take a look at the statistics function you mention...

Thanks!

But first I have to get Magick++ working (viewtopic.php?f=1&t=12240)!

/ Mikael

Can't seem to find any statistics function... where should I look?

See http://www.imagemagick.org/Magick++/Image.html and look for the statistics() method description:

statistics
ImageStatistics *statistics
Obtain image statistics. Statistics are normalized to the range of 0.0 to 1.0 and are output to the specified ImageStatistics structure. The structure includes members maximum, minimum, mean, standard_deviation, and variance for each of these channels: red, green, blue, opacity (e.g. statistics->red.maximum).

That's wierd!

I just had that very same page open and I did a search for statistics (several times actually) without hits. I opened your link in another tab and compared the two. In the first tab the statistics function was actually missing

...until I reloaded the page, then it appeared.

Is my browser playing a joke on me, or did you just update the page?

Anyway, thanks for the help!

/ Mikael

Hi Guys,

For what it is worth, I just found a way to get TIF page count by using the Shell.Application object (in VB and WinXP in my case)...

Code: Select all

    Dim aryArray() As String
    Dim objShell
    Dim objFolder
    Dim strPC As String
    Dim strDM As String
    Dim objFileName
    Dim strRowSource As String
    
    Set objShell = CreateObject("Shell.Application")
    Set objFolder = objShell.NameSpace("C:\FOLDER\")

    For Each objFileName In objFolder.Items
        strDM = objFolder.GetDetailsOf(objFileName, 3)
        strPC = objFolder.GetDetailsOf(objFileName, 13)
        strRowSource = Chr(34) & Format(CDate(strDM), "MM/DD/YY HH:mm AM/PM") & Chr(34) & ";" & Chr(34) & strPC & Chr(34) & ";" & strRowSource
    Next

There are actually 33 Details. They are the same ones you see in windows explorer when you right-click on the columns and select what columns you want to view. In my case, I just got the "Pages" one which is 13 and the date created which is 3.

Other info:

0 Name
1 Size
2 Type
3 Date Modified
4 Date Created
5 Date Accessed
6 Attributes
7 Status
8 Owner
9 Author
10 Title
11 Subject
12 Category
13 Pages
14 Comments
15 Copyright
16 Artist
17 Album Title
18 Year
19 Track Number
20 Genre
21 Duration
22 Bit Rate
23 Protected
24 Camera Model
25 Date Picture Taken
26 Dimensions
27 ?
28 ?
29 Episode Name
30 Program Description
31 ?
32 Audio sample size
33 Audio sample rate

removed/ mistakes...

Legacy ImageMagick Discussions Archive

Count color pages of TIFF image

Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image

Re: Count color pages of TIFF image