Getting back to the image compressor WinForms app while on a train

2023-02-13

I went to ComboBox1 properties and opened the Items (Collection) to see just one line "JPG". I replace that with lines: Jpeg JpegCMYK Gif GifCMYK Webp WebpCMYK Heif HeifCMYK

Added to Codec() method:

        Dim format
        Select Case ComboBox1.SelectedValue
            Case "Jpeg", "JpegCMYK"
                format = ImageFormat.Jpeg
            Case "Gif", "GifCMYK"
                format = ImageFormat.Gif
            Case "Webp", "WebpCMYK"
                format = ImageFormat.Webp
            Case "Heif", "HeifCMYK"
                format = ImageFormat.Heif
            Case ""
                format = ImageFormat.Jpeg
                ComboBox1.SelectedValue = "Jpeg"
            Case Else
                Throw New ArgumentException(ComboBox1.SelectedValue)
        End Select

Added to Params() method:

        Dim formatName As String = ComboBox1.SelectedValue
        If formatName.EndsWith("CMYK") Then
            Dim cmykTrue As Short = True
            param = New EncoderParameter(Encoder.SaveAsCmyk, cmykTrue)
            obj.Param(1) = param
        End If

It then turned out I may need to add a Nothing case to the "" empty string case. And then it turned out that despite Codec and Params being called to supply argument values in that order, Params seems to be called first or simultaneously. I decided to localize the variable to ensure Codec gets called first.

While trying to test that, I accidentally chose an mp4 file instead of an image: so it turned out, I needed to catch System.OutOfMemoryException on the Image.FromFile call.

        Catch oom As OutOfMemoryException
            MessageBox.Show("
              The file has given us an OOM because of its sheer size.
              Goodbye.
            ", "File too large", MessageBoxButtons.OK, MessageBoxIcon.Error)
            Close()
            Return
        End Try

I then decided to make the earlier things

And only then I debugged and it turns out I should have used `SelectedItem` everywhere, instead.

And I then added a handler for ComboBox1.SelectionChangeCommitted that just calls Render().

I then moved the `Dim formatName` in `Params` to the top and made the EncoderParameters constructor get a

instead, and then I made the IDE abstract the EndsWith into a method along with getting the SelectedItem, and then inlined the variable, just to get

    Private Function isCMYK() As Boolean
        Return ComboBox1.SelectedItem.EndsWith("CMYK")
    End Function

I then made Codec() return

instead, and that will have to be handled, so

    If result Is Nothing Then

        format = ImageFormat.Jpeg

        MessageBox.Show($"Format has been set to jpeg because {ComboBox1.SelectedItem} was not available in the system.")

        ComboBox1.SelectedItem = "Jpeg"

        result = getTheFormatFromCodecs(format, codecs)

    End If

having had extracted a method out of the Select with FirstOrDefault, but still using the `codecs` array, while I should cache both from the start really.
And we will just have to start with checking which are available and removing them from ComboBox1's Items Collection.

I then decided to add a simple

at the end of Render(). Worked liked a charm and shown us that the Quality parameter doesn't affect Gif, nor does our CMYK Jpeg option change a thing as the sizes are the same as with non-CMYK. We gotta implement saving to be able to actually inspect things as files.

See me with an external display in a train:

=> 2023-02-13--195551--img.jpg