PNGReaderMBS.ApplyOptions(gamma as double = 0.0, ScreenGamma as double = -1.0) as boolean

The gamma parameter defines what gamma correction is applied:
positive value: use the value as the gamma correction
zero: use default value (or value saved in file itself)
negative value: do not correct gamma

Added ScreenGamma parameter in plugin version 15.2. If you set both gamma and Screengamma to a value > 0.0, the plugin will use those gamma values. If both are equal, no gamma correction is made.

16-bit images are always reduced to 8-bit images.

Returns true on success and false on failure. Calls ReadHeader method if needed.

Some examples using this method:

• /Images/JPEG/PNG to JPEG with ICC Profile
• /Images/LargePicture/PictureMBS display huge picture
• /Images/LargePicture/PNG Load and Save
• /Images/PNG/Load iPhone PNG/Load iPhone PNG
• /Images/PNG/PNG Load To MemoryBlocks
• /Images/PNG/png with profile

PNGReaderMBS.CombinePictureWithMask as picture

PNGReaderMBS.Open(file as folderitem, data as string) as boolean

Returns true on success.

PNGReaderMBS.OpenData(data as string) as boolean

Returns true on success.

PNGReaderMBS.OpenFile(file as folderitem) as boolean

Var p As New PNGReaderMBS
Var f As FolderItem = SpecialFolder.Desktop.Child("test.png")

If p.OpenFile(f) Then
  If p.ApplyOptions Then
    If p.ReadPicture Then
      window1.Backdrop = p.Pict
    End If
  end if
End If

Returns true on success.

See also:

• OpenFile(Path as String) as boolean

PNGReaderMBS.OpenFile(Path as String) as boolean

Var p As New PNGReaderMBS
Var f As FolderItem = SpecialFolder.Desktop.Child("test.png")
Var path As String = f.NativePath

If p.OpenFile(path) Then
  If p.ApplyOptions Then
    If p.ReadPicture Then
      window1.Backdrop = p.Pict
    End If
  end if
End If

Returns true on success.

See also:

• OpenFile(file as folderitem) as boolean

PNGReaderMBS.OpenSpecialData(data as string) as boolean   Deprecated

Var f as FolderItem = getfolderitem("mbs.png")
Var b as BinaryStream = f.OpenAsBinaryFile(false) // BinaryStream.Open(f) in newer RB versions
Var s as string = b.Read(B.Length)

Var p as new PNGReaderMBS
if p.OpenSpecialData(s) then
  if p.ApplyOptions(0) then
    if p.ReadPicture then
      Backdrop = p.Pict
      Title = "OK"
    else
      Title = "Failed to read picture."
    end if
  else
    Title = "Failed to apply options."
  end if
else
  Title = "Failed to open picture."
end if

This function can be used to read PNG files made for the Apple iPhone. The PNG is converted from the Apple format to the normal PNG format and passed to OpenData. In the SourceData property you can get the modified PNG data. Still this modified PNG data has the channels swapped, so you should read the image with the pict property.

On Mac OS X 10.8, the NSImage class also reads iOS optimized PNG files.

Deprecated as it does not read all files and we can't fix this old code. Please use a command line tool to convert instead.

PNGReaderMBS.ReadEXIF(byref exif as string) as boolean

Returns true on success or false on failure.

PNGReaderMBS.ReadHeader as Boolean

This reads header and fill properties Width, Height, ColorType, OriginalColorType, InterlaceType and BitDepth.
Returns true on success and false on failure.

PNGReaderMBS.ReadICCProfile(byref name as string, byref compression as Integer, byref profile as string) as boolean

Name is the profile name, compression the method used to compress the profile data and profile a string with the content of the profile as binary data.
Returns true on success.

Some examples using this method:

• /Images/JPEG/PNG to JPEG with ICC Profile
• /Images/PNG/png with profile

PNGReaderMBS.ReadPicture as boolean

Returns true on success.

Some examples using this method:

• /Images/JPEG/PNG to JPEG with ICC Profile
• /Images/PNG/Load iPhone PNG/Load iPhone PNG
• /Images/PNG/PNG Load To MemoryBlocks

PNGReaderMBS.ReadRow as memoryblock

Var fSource as FolderItem = SpecialFolder.Desktop.Child("test.png") // some png with alpha
Var oPNGInput as new PNGReaderMBS

If oPNGInput.OpenFile(fSource) Then
  If oPNGInput.ApplyOptions(0) Then
    
    Var imgSource as New PictureMBS(oPNGInput.Width, oPNGInput.Height, PictureMBS.ImageFormatRGBA)
    
    ' Read row by row the file and puts it in a PictureMBS instance
    
    Var nMax as Integer = oPNGInput.Height - 1
    For nInd as Integer = 0 To nMax
      imgSource.RowInFormat(nInd, PictureMBS.ImageFormatRGBA, true) = oPNGInput.ReadRow()
    Next
    
    ' show only alpha/mask channel
    Backdrop=imgSource.AlphaChannel.CopyPicture
    
    ' show Picture without mask
    Backdrop=imgSource.CopyPicture
    
    ' show picture with mask
    Backdrop=imgSource.CopyPictureWithMask
    
  End If
End If

Returns nil on any error.
Format is RGBA as in the example with 4 bytes per pixel.

See also:

• ReadRow(mem as memoryblock) as boolean

Some examples using this method:

• /Images/LargePicture/PictureMBS display huge picture
• /Images/LargePicture/PNG Load and Save
• /Images/PNG/PNG Load To MemoryBlocks
• /Images/PNG/png with profile

PNGReaderMBS.ReadRow(mem as memoryblock) as boolean

Returns false on any error and true on success.
Format is RGBA as in the example with 4 bytes per pixel.
Make sure the memoryblock is big enough. Else you risk a crash.

See also PNGReaderMBS.RowBytes.

ReadRow with reusing memoryblock is faster than allocating a new one for each row.

See also:

• ReadRow as memoryblock

PNGReaderMBS.ReadRowAlphaOnly(mem as memoryblock) as boolean

Returns false on any error and true on success.
Format is alpha channel as in the example with one byte per pixel.
Make sure the memoryblock has size from RowBytes property. Else you risk a crash.
The data in memoryblock is width bytes long, 1/4 of the size of the memoryblock.

See also PNGReaderMBS.RowBytes.

ReadRow with reusing memoryblock is faster than allocating a new one for each row.

PNGReaderMBS.ReadRowMaskOnly(mem as memoryblock) as boolean

Returns false on any error and true on success.
Format is mask (inverse alpha) as in the example with one byte per pixel.
Make sure the memoryblock has size from RowBytes property. Else you risk a crash.
The data in memoryblock is width bytes long, 1/4 of the size of the memoryblock.

See also PNGReaderMBS.RowBytes.
ReadRow with reusing memoryblock is faster than allocating a new one for each row.

PNGReaderMBS.ReadsRGBTag(byref file_srgb_intent as Integer) as boolean

Returns true if the value was read into the given variable.

Some examples using this method:

• /Images/PNG/png with profile

PNGReaderMBS.RowBytes as Integer