Work flow for preparing digital images

spm12spm03bThe .jpg shown in that view is the final output from the process.   Normally one would follow this process with a batch of files, but in this example, just one file is used.

1/ To remove height, rotational and other errors between the left and right images, in SPM, use Multi Conversion on the input files (.MPOs or .JPGs, dependent on where they come from) with just Auto alignment and Auto crop after adjustment boxes ticked. Set the auto alignment settings to mount near points to the window if deviation is less than 1/25th image width. Save the resulting images to a suitable new folder. Use Output file type = TIFF (uncompressed) if you can afford the disk space, otherwise .JPG @ say 85% quality.

spm01spm02How to set up the rest of the Multi Conversion parameters.  Look for ticked boxes and the Output Folder identity  Click “Convert all files” to start the process.

The next three images are what you should observe once the process has started.





Conversion completed.  The process will leave the aligned .jpg file in sub-folder SbS.

2/ Next, for editing the overall picture, in SPM, use Open Stereo Image to view each image in turn to decide what editing is required. This may include cropping, rotation (for those like me who keep holding the camera tilted) and adjustment of the near points to the window (as SPM auto-alignment gets close but not perfect!). Easy Adjustment from the adjust pull down menu offers all of these adjustment types and more, and Auto Colour Adjust is good for fixing L/R differences arising with SDM rigs (check the result for “artefacts” (spurious image effects) before saving and be prepared to “undo”)
If you have a Zalman screen on your computer, use this (with SPMs 3D interlaced mode) to view your images, and don’t use the easy adjustment feature to adjust the near points to the window – simply use the keyboard’s left and right arrow keys to get real precision with your window adjustment. When all this is done, switch back to Side-by- Side mode, then use Save Stereo Image to over-write the image you got from Multi- conversion. These are now your fully corrected images and may be re-formatted for various different forms of presentation – so don’t over-write them!


The image in the SbS sub folder as opened by “Open Stereo Image”

spm05The Easy Adjustment window.  Final adjustment to the Stereo Window requires the use of anaglyph glasses and the slider at the top right of the window. The “rotation” control here is also useful.


What you see if you have a Zalman screen or similar that displays using interlaced mode (click the horizontal-striped icon near the middle of the tool bar to select this view)  Obviously you need polarised glasses to see this in 3D!

The next three screen shots show the steps in saving the windowed image (Save Stereo Image) – Note that it overwrites the SbS image resulting from the earlier multiconversion.




NB Latest versions of SPM in the ‘Save Stereo Image’ window there is a tick box bottom left corner ‘Always save SBS format’ Tick this and you don’t have to worry about switching between interlaced and side by side before saving.

Steps 1 and 2 are suggicient for images to be used in Magix, Sony Movie Studio and other programmes which are designed to handle 3D images

Only proceed to steps 3 and 4 if working with Pro Show, P2E and other programmes unaware of 3D content

3/.Resize the images to 2800 x 1050 or a larger 8:3 format. This can be done with Multi Conversion but this time, we need to check only the Resize box and the keep designated size box and click the border button. Enter the required size of one half of the image width in the width box and the height in the height box (e.g. 1400 and 1050). [SPM works with figures for just the left (or right) image] Be sure to define a new output folder, e.g. “resized 2800 x 1050”


Shows which boxes and bullets to tick/click in the Multi Conversion window.  Note that the Resize width and height boxes are too narrow for 4 digits to be displayed:  400 is actually 1400 and 050 is actually 1050.  Note also that SPM works in terms of the size of one image, not the combined SbS image (1400, not 2800)  The output folder needs to be defined (SbS_2800 x 1050).   Click “Convert all files”.


The end of the process.  Click exit.  Your files are ready for use.

/. If you have chosen 2800 x 1050, these images are ready for insertion into a simple show. 5/. I do not intend to go into detail here on show preparation using Magix, Vegas, ProShow or P2E. The main things that must be correct for projection purposes for all of these are the show format and the export format.
Show Format:
For ProShow and P2E, this is set in the New Show dialogue by selecting “Custom” and 2800 x 1050. In Magix , in the Create New Show dialogue, under Movie Settings , select :PAL HDV2 1080i 16:9 ( 1440 x 1080; 25fps)

Exporting Executable files:
When creating an executable file in ProShow, in the Create Executable dialogue, set the window size = 2800 x 1050. In P2E, the Create Executable dialogue has no entry for format and uses the Show format. Magix and Vegas do not make executable files.

Exporting Video Files:
When exporting video files from these applications it is also essential to select the appropriate format.
In Magix, e.g. in the Windows Media export dialogue, select resolution: 2800 x 1048 (this is closest available and works OK) and Stereo3D: “side-by-side left pic on left”. In ProShow , Publish For Computer Custom Video File, set Type: Custom, Format: AVI compressed, Compression Xvid MPEG4, Resolution: 2800 x 1050, Frame Rate: 25, Aspect Ratio: square pixels.

The above approach is not the only way, but it works for me. Please feel free to contact me for more information if you find this insufficiently clear.

Mike Hillyard