How do i improve quality of image created by append front panel image to report vi.

[randy1815]

How do i improve quality of image created by append front panel image to report vi.  Some lines in plots are slightly blurry.

[Robbob]

Randy,

The append front panel image to report vi has three file output options: jpeg, gif, and png. The default is jpeg, which can lose quality when transferred. Have you tried the other two file types? PNG should provide the best compression(lossless) according to several websites and through personal experience.

[randy1815]

Thats a good point.  I know that I can't use GIF because they can't be included in stand alone applications per the help file.  I have switched to the PNG and will try it. It looks a little better in the word file when ran on the development machine. I'll have to test for the application to see if it works there. I have never used that type before.  Still curious if there is a way to change the compression on the jpeg. As always thanks for the help.

[NimbleThink]

The encoding algorithms used for JPEG are designed for photographs whereas the encoding algorithms for GIF and PNG are designed for graphics.

Take the example of an image of plotted data with an X and Y grid.

Consider the leftmost 8 pixels in every line.

Every 10th line in the plot might have a black horizontal line and the other 9 lines might be white with a single black pixel (for the vertical Y-axis).

Such graphical elements may be compressed greatly by storing one instance of the "8 black pixels" and one instance of "6 white pixels, 1 black pixel, 1 white pixel".

Whereas such an algorithm would function poorly for photographs where there are <blobs> of color with amorphous edges consisting of color gradients.  Every line in a blob would require a separate set of 8 pixels to be recorded.

So try taking a photo and saving in both JPEG and PNG format: the PNG will be much larger.

Now try taking a black grid/white background/blue data points plot of data and save with both JPEG and PNG.  The PNG will be substantially smaller and look better.  This also holds true for any charts you generate in Excel or other programs: save them in PNG and they will be the smallest (smaller than BMP even), and pasting plots as PNG into web pages or PowerPoint instead of JPEG (or BMP) will result in smaller and faster HTML pages/PowerPoint slides.

Given the optimal image formats for photographs versus graphics & icons it is perplexing why NI did not make PNG the default image format for front-panels, block diagrams, and VI icons in reports.

Regards,

Leif Kirschenbaum