CineFrameCatcher - Help

CineFrameCatcher Version 2.0 2020-06-21 ---- Copyright © Wolfgang Kurz, 2020

Table of Content

Introduction

The CineFrameCatcher is a program to support the digitization of cine films in 8 mm,  9,5 mm (Pathé) and 16 mm format. 9.5 mm and 16 mm formats are currently implemeted but not fully tested, because I have not the ressources to do that. At that point I want to thank Lawrence Cockell who supported me especially in the area of Pathé and Arduino testing.

The frames of a cine film are caught separately by a video capturing device (digital microscope or similar) and stored with consecutive numbers in a frames directory to allow later (in a separate step) to generate a video in SD or HD format with a video generation program (e.g. VirtualDub together with AviSynth)

Hardware Prerequisites

To catch the frames of a cine film you need a special hardware which is unfortunately not available as fully assembled device that can be bougth. It must be crafted by yourself, but this is not very difficult if you have a little crafting experiance.

As components to build the device you need:

1. A digital microscope.

For good quality frames the camera of the microscope should have at least 1.3 Megapixel. This allows a video resolution of 1280 x 1024 pixel. You can achieve also a higher resolution when exploiting 5 MP cameras, but this does not necessarily improve the quality of the final movie.
I use a Celestron Digital Microscope 5 MP (right image), good is also a Celestron Digital Mikroskop 1.3 MP (left image).

   

2. A stepper motor to move the film through the transportation unit

Suitable are bipolar 2-phase stepper motors (about 1 to 2 Ampere) with a 1.8° step angle and 200 full steps per revolution
or (for slightly improved accuracy) 0.9°step angle and 400 full steps per revolution e.g from NanoTech or Trinamic.

3. A stepper controller

Suitable are controllers driven by an Arduino UNO board (left image) and appropriate motor shield ( e.g. an Arduino motor shield or an Adafruit motor shield) as final output stage (central and right image)
or integrated motor controlers e.g. the Trinamic StepRocker TMCM-1110 (a controller with integrated final output stage - lower image).


Normal 1.8° stepper motors achieve when performing fullsteps an accuracy of positioning of about 5%. I therefore recommend a Trinamic StepRocker TMCM-1110. It operates with microsteps (256 per fullstep) and by that you can achieve a better positioning accuracy.

4. A sprocket wheel with 8, 10, 16, 20 or 25 sprockets

The transport of the film must be done frame-wise exploiting a sprocket wheel for transportation with either 8, 10, 16, 20 or 25 sprockets which fit into the perforation of the film.
(If you use a different number of sprockets you have to code the transportation sketch (script) for your controller yourself.)
You can get fitting sprocket wheels from old projectors or viewers if you take broken devices appart. Alternatively you can use a 3D printer to print a plastic sprocket wheel with the desired number of sprockets. Keep in mind: a smaller number of sprockets is better than a higher number, because you can use a higher number of steps to position the wheel. In the internet you can find offerings for files you can use to print the wheel in all desired dimensions. The right image shows examples of 3D printed wheels. The left image shows a sprocket wheel made from aluminum with an adapted thick axle used to drive the catcher wheel with a textile enforced rubber belt.



Experienced do-it-yourselfers owning a well equiped workshop may also create a tranportation grabber according to the following sample (see image):
(The sketch for this grabber is from Claus Kappe ! Hint: Rotation clockwise. The grabber moves a single frame per one full motor revolution by inserting a little pin into the perforation of the film. This is a very precise movement. It is comparable to the grabber in the film camera.).

5. A illumination unit.

For the illumination of the transparent film frames you need a light source with a neutral light color (5000° Kelvin or even higher) - warmer light source - below 5000° Kelvin - causes the scanned images to appear slightly red. A bulb with 150 to 200 Lumen (2 Watt LED bulb) is normally sufficient. There are several possibilities, e.g. an OSRAM LED GU10 Reflector 2,6 Watt, DC 12 Volt Light bulbs with Transformer or USB LED bulbs. You can also exploit the LED ring of the microscope, if it has one. Even a single daylight white LED, if placed correctly, might do.
If the light is too bright, you can use a piece of white cardboard as diffuser to adjust the illumination to the needs of the microiscope used.

                 

6. A power supply.

To provide the correct power to the unit you need a power supply providing 12 Volt and about 2 Ampere current. Suitable are power supplies which are capable also to provide 5 Volts e.g. for the illumination when using little LEDs and potentially for running a catching wheel motor. Power supplys of external 3.5" HDDs are a good choice, they are strong enough.

7. A 5 Volt DC (direct current) motor (optional)- probably with a gearbox .

To drive the catching reel you can use a transmission, which is operated by the stepper motor as well (a textile enforce rubber belt will do. You will find it in the sewing kit of your wife.) But you can also use an independent 5 Volt DC motor.
The required power on/power off controlling is provided in the attached Arduino sketches, but it can also be implemented for the StepRocker board.

8. A 4 way focusing rail

For an optimal positioning of the microscope over the frame window it is good practise to use a 4 way focusing rail as it is used in the macro photograpie as a tripod head or a Microscope stand with positioning screws (e.g: Conrad Order-No: 191348 - 62 )

   

A complete transportation unit

The microscope is placed above the frame window using the 4 way focusing rail. It can be moved precisely in all 3 dimensions with this device. This allows an exact positioning above the frame window and a perfect focusing of the lens can be achieved. Good focusing is very important, because the depth of field is minimal for a focus length of only several millimeters. You must be able to precisely move the microscope up and down within a range of 100 to 200 micrometer.
The film is guided below the microscope and above the illumination chamber on a film guidance rail. For the film guide see image below.



Below the film guidance and the microscope the light chamber is located. Inside the light chamber there is the illumination unit (light bulb). Between light bulb and frame window you may have to apply a diffuser (e.g. a piece of bright white paper - 80 to 160 gr) to achieve an evenly illuminated area as background for the frame to be grabbed.

Left of the light chamber there is the transportation unit located. It is shown here whit a grabber. Instead of the grabber you can also use the sprocket wheel which is like the grapper driven by the stepper motor.

Even more to the left you see the capture reel which is driven here by a transmission. If you like, a 5 Volt DC motor can also be used. It will be controlled via the StepRocker. The CineFrameCatcher provides the required electronic signals to the StepRocker.

Software Prerequisites, Installation and Invocation

The CineFrameCatcher is a Windows application developed using MS Visual Studio Community 2019, C# as programming language and .NET Framework 4.6.1 as class library (the runtime components of .NET 4.6.1 or better must be installed, to run the application properly). The components of the Accord .Net Library 3.8.0 must also be installed (the required components are contained in the distribution file) and if the Arduino board shall be used, the components of the Solid.Arduino Library (it is also contained int the distribution file) must be installed as well.
The application can be run on a computer with a MS Windows operating system (Windows 7 or higher, preferably Windows 10 64 Bit). You can the application also install under a Virtual Machine (Oracle Virtual Box or VMWare ...).

The application is delivered via an installation file compressed by 7-Zip. To install the application, it is sufficient to unpack the installation file into an installation directory of your choice, e.g. to C:/Windows/Programs/CineFrameCatcher.
The Windows registry is not used.
For potential updates it is normally sufficient to replace the CineFrameCatcher.EXE file in the installation directory.
De-Installation is simply done by deleting the installation directory with all it's content.

For the program invocation you can create a desktop shortcut. Suitable icons to identify the shortcut easily are provided via the installation file.
Annotation: The application is protected against multiple invocation. It can be executed on a computer only once. An attempt to run the application simultaneously a second time will be postponed, until the first invocation has been terminated.

In the desktop shortcut you can provide three invocation parameters:

1. A logging control character. "0" = Logging switched off and "1" = Logging switched on. 
2. the execution languages supported are currently"EN" for English and "DE" for Deutsch (German).
   and
3. the path to an existing directory (the base directory), into which the application files (the project directory with their subdirectories "FRAMES" and "VIDEO") are placed which are created for each project.

To set a new and meaningfull desktop icon in the shortcut, you can use the icons provided in the installation directoy.

Running the Program

Starting the Application

The application is started either

1. via the EXE file (eventually as described in the example below with the shown invocation parameters) in the batch command window. Take care about the installation directory!
   Example for the batch invocation command C:/Programs/CineFrameCatcher/CineFrameCatcher.exe "EN" "1" "E:/FilmProjects"
   or
2. via the desktop shortcut as described above.

As already mentioned, the application can be active only once to prevent images that should be grabbed to be overwritten.

The Main Window

The first window presented is the main window. It provides a menu bar and a message field as well as all required input fields to control the frame capturing, grouped into 3 categories.

These groups are:
1. the Project Parameters
2. the Transport Parameters
3. the Video Device (Catching) Parameters

The Menu Bar in the Main Window

the menu bar contains three main groups: 1. File, 2. Options and 3. Help

The menu "File" comprises 3 entries.

1. Select language
2. Create new project
3. Exit

The menu "Options" comprises 7 entries.

1. Generate AVS File for VirtualDub
2. Show actual parameters
3. Erase all images in the image subdirectory
4. Enable logging
5. Disable logging
6. Show logfile content
7. Clear Logfile content

The menu "Help" comprises 4 entries.

1. Stepper positioning
2. CineFrameCatcher Help
3. Test for updates
4. About CineFrameCatcher

File menu items

Select language

The presentation language of the application can already be defined in the invocation parameter. But if - due to special reasons - a different presentation language should be used, you can via this menu selection switch to the newly desired language. Currently (as of June 2020) only two languages are implemented Deutsch (DE) and English (EN).

Create new project

If this menu item is clicked, the input fields ( new PID ) needed to create a new project are shown in the "Project Parameters" section.
You can enter the 4 character idetification of the new project in the new PID field and the required folders are created in the base directory.



Exit

Via this menu entry the running program will be terminated. All open windows of the application will be closed too and the actually valid input values are saved in the applications INI file located in the installation folder.

Generate AVS File for VirtualDub

Via this menu item a file is generated with the parameters needed to generate the video clip exploiting VirtualDub in combination with AviSynth.
The file with a name composed from the project ID and the actual Frames subfolder is located in the project's VIDEO folder. It can be used as video input file in the VirtualDub "File-> Open video file" menu item.


Show actual parameters

This menu entry calls a message box which shows the actual content of the INI file to allow the verification of these values. (The constants for the first field initialization are based on the saved values of the preceding session). If a new project (different from the previous one) is started, you can check, if the values used for initiation are correct or if they have to be adjusted.




Erase all images in the image subdirectory

This menu entry causes the deletion of all images in the actually active image subdirectory. The request must be confirmed via pressing OK in the upcoming message box. Only the existing files are deleted. Potentially existing subdirectories will be kept.

Enable logging

Via this menu item you can enable the logging of application events if logging is currently not active. This is only possible, if the logging file is not reserved by a different process, e.g. a text editor like Notepad or Notepad++

Disable logging

Via this menu you can disable a currently active logging function.

Show logfile content

As a logfile normally contains a lot of entries, this menu entry does not really present the content of the logfile, It reminds you, that you can view the logfile with a text editor like Notepad or Notepad++.

Clear logfile content

Via this menu item you should be able to erase the complete content of the active log file.

Options menu items

• Position stepper

  This menu item tells you how you can easily position the stepper motor to a desired angle even if it is blocked by a holding moment. This is especially useful if you use a grabber instead of a sprocket hole.

  
  
  
• CineframeCatcher help

  Via this menu entry the CineFrameCatcher Help file is presented in the web-browser format.

  
• Test for Updates

  Via this menu entry it can be checked if the most recent version is installed. The computer must be connected to the internet. If a new version is present in the internet, also during the application start a message is presented in a message box..

  
• About CineFrameCatcher

  This dialog shows the most important information about the CineFrameCatcher application

  

The Project Parameter Pane

The project parameter pane shows all input fields related to and describing the catching project.

Field names and field functions

Base directory
The base directory is a global directory into which all project folders including their subfolders should be located. A project folder is named by a name with 4 characters e.g. "TEST". A project folder at least has 2 subfolders. This are the subfolder FRAMES and the subfolder VIDEOS. The subfolder FRAMES itself has several subfolders named by a single character e.g. "0", "1", "2", "3", and so on. These FRAMES subfolders are used to speed up the processing, because folders that contain more than 10000 files tend to become relatively slow during processing. As a film easily can comprise 30000 to 50000 images it makes sense to divide this large number of image files into several processing groups. The frames of such a processing group are stored in such a FRAMES subfolder.
Project-ID
The 4 character project-id is the name of a digitization project. The 4 characters should provide a meaningfull abbreviation for the project. For instance IT73 could be used for "Vacation in Italy 1973". The project name is also the designation of the project folder, which is stored as subdirectory in the base directory. The drop-down field shows all project id's contained in the base directory.
New Project-ID
If via the menu item "File -> Create new project" a new project shall be created, an additional input field shows up, into which the new project-id (again only 4 characters) has to be entered. A new project directory with the entered name is inserted into the base directory and the "FRAMES" and "VIDEO" subdirectories as well as a subdirectory "0" in the "FRAMES" directory are created for it.
Subdir (1 char)
This is a subfolder of the "FRAMES" directory for the frames associated to a certain processing group of a project. A new subfolder can be created via button "new". The subfolder is created and selected immediately. Subfolders are created in numeric and alphabetic order. A subfolder "1" is followed by the subfoler "2", the subfolder "2" is followed by subfolder "3", the subfolder "9" is followe by subfolder "A" and subfolder "A" is followed by subfolder "B" and so on.
The drop down list field shows all existing subfolders of a "FRAMES" directory of a certain project.
Film-Type
The film type determines, how the images of a film must be captured. The following film types can be selected via the provided checkmarks:
1. Super 8 and Single 8 movies ( S8 )
2. Normal 8 or Regular 8 movies ( N8 )
3. Pathé [9.5 mm] ( Pathé ) - implementation currently not fully tested due to the lack of the needed footage
4. 16 mm movies ( 16mm )  - implemented currently not fully tested due to the lack of the needed footage


This are the parameters used to extract the frames for the various film formats:

Image-Type

The grabbed frames of a film may be stored in two different formats. These formats are:
1. The JPG or JPEG format (from Joint Photographic Experts Group) is a format in which images are stored lossy but very compact. JPG images are according to the compressing strength relatively small - movie frames in SD or HD resolution need between 30 KB and 100 KB storage.
2. The PNG format (from Portable Network Graphics) is a format, in which the images are stored lossless but still somehow compressed. PNG images are about 10 times larger than JPG images but smaller than uncompressed BMP  or TIFF format images (BMP = Bitmap raster graphic format of Windows, TIFF = taged image file format - owned by ADOBE).
JPG-Qual
The JPG quality reflects the compression strength of a JPG image. The smaller the number, the higher the compression.
Good compression values, which do not result in poor image presentation, are 80 to 90. 100 means, the image is not compressed.


Sharpening parameters
CineFrameCatcher provides two functions to sharpen the grabbed images, standard image sharpening (left image) and gaussian sharpening (right image). It is recommended to use the standard image sharpening. Gaussian sharpening very often highlights borders in an image too much, so that the images show very exaggerated.

Buttons of the project parameter pane

The pane has 3 buttons. These are:

1. Find base directory
   Via this button the System Directory Search Dialog is activated. Here the project base directory can be selected. Rem
   Remark: the base directory is the root directory of a project. If there are already projects stored, do not select one of the probably existing project directories.
2. Create new project ( actually a File-> menu item)
   Via this menu item ( File -> "Create new project") an input field is activated, in which the new project id can be entered to trigger the creation of a new project.
3. New Subdirectory
   Via this button a new subdirectory with the next free 1 char number is created in the FRAMES folder of the actual project. The new subdirectory is incorporated in the Subdir drop down field and it is immediately activated as current subdirectory.

The Transport Parameter Pane

The transport parameter pane shows all input fields related to and describing the film transportation during Catching project performance.

Field name and field function

Select COM-Port
In this drop down list field all in the computer existing and active serial ports are listetd.
The list is filled or refreshed using the "find" button next to the drop down list. Via this list the serial port must be selected to which the transport controller (Arduino, StepRocker etc.) is connected.
If the transport control board is not active (is not powered), the serial port is not displayed. The board must be powered first and then you have to search for the serial port and connect it to the board..
Note: In Windows 10, a new INF, Usbser.inf, has been added to %Systemroot%\Inf that loads Usbser.sys as the function device object (FDO) in the device stack. If your device belongs to the Communications and CDC Control device class (e.g. the StepRocker), Usbser.sys is loaded automatically.
Number of sprockets
Via this field is defined, how many sprockets of a sprocket wheel have to be used. Supported are 1, 8, 10, 16, 20 and 25 sprockets.
If a grabber device is used to transport the film normally "1" must be selected. "1" transports one frame per one full revolution of the motor.
If for the transport of the film a sprocket wheel is used, then 8, 10, 16, 20 or 25 must be selected, depending on the number of sprockets your wheel has.
Board
Via the checkboxes in the "board" section the program is told, which kind of transport control board is used.
If "StepRocker" is checked, a control board like the Trinamic StepRocker TMCM-1110 is installed. These controllers normally have their proprietary control language. The StepRocker uses TMCL (the TRINAMIC Motion Control language). The needed commands for the transport with the StepRocker are generated by the CineFrameCatcher.
If "Arduino" or "Adafruit" is checked, then a control board of the "Arduino" type (Arduino UNO or similar) is connected. The Arduino boards are programmed by a special JAVA script/sketch. This scipt also controls the motor shields (Arduino, Adafruit or similar),. A sample sketch is provided, but in some cases it might be required to programm the sketch on your own.
The CineFrameCatcher uses a special format of the transport trigger command that contains information about the step type, the transport direction, the number of steps to move, the speed to be set to the motor and (if needed - instead of the speed) the time delay between steps. This information has to be read by the transportation controlling script, the Information must be interpreted and transformed to the form required by the motor control shield.
Special StepRocker parms
There are two special parameters for the StepRocker board. These parameters control the rotation speed and the acceleration of the wheel, when started. Both values can be set with a value between 1 and 2047. The higher the number, the faster the speed and the acceleration. The maximum values are a good selection for frame extraction.
Special Arduino parms
If Arduino or Adafruit is checked, you can select the transport speed by setting the speed rpm in rotetions per minute. The higher the value, the faster the transport.

By clicking the button Arduino/Adafruit cmd you generate the Arduino command form the defined parameters. You can see the generated command in the message field displayed at the window top.

Transport delay between frame captures
After a film has been transported by one frame with the transportation device, several processing steps have to be performed consecutively. First the frame has to be grabbed by the video camera, then the image most likely has to be sharpened and sometimes it also have to be rotated. In most cases the image has to be resized and finally it has to be stored in a folder on a hard disk or other storage media. This are all activities, which need - dependent on the power of the exploited computer - a certain time span (delay time).
With this parameter you can set a time span, the motor has to wait until the next transport can be started. If this time span is to short, than distortions in the image can occur, because the image is already caught as long the transportation is still ongoing. It makes sense to test the needed time for the actual hardware in steps of 50 milliseconds.



Read timeout
With this parameter value (in illiseconds) you can set the time interval available for the controller to read the commandthat was send by the CineFrameCatcher. Values between 1000 and 5000 milliseconds seem to be OK.
If the StepRocker Controller is connected via TS485, tha a value of 1000 milliseconds or below should be used. This value significantly determines the speed, whith wich the frames xcan be scanned.
Fullsteps / Revolution
This is the definition of the type of stepper motor exploited. 1.8° stepper motors (the most common type) need 200 fullsteps for one revolution. A little bit more accurate are 0.9° stepper motors, they need 400 fullsteps for one revolution. Motors with a larger step angle should not be used, because with such motors the positioning accuracy of the frames is too poor.
Block (currently not used)
If this is checked, the axle of the motor is blocked. That means, a holding momentum (full torque) is applied to the motor and it can not be rotated manually. Note: this must be supported by the Arduino script used.
No.MS per FS (number of microsteps per fullstep)
This field determins in how many microsteps a fullstep can be devided. Common values are 16 or 256 dependeing on the used stepper motor.
Move direction
The transport parameters define the rotation direction (forwards or backwards) that has to be applied to transport the film correctly through the catching device.
Step type
Stepper motors can be operated in several modes. The modes are fullstep, halfstep and microstep. For a 200 steps motor a fullstep causes the axle to be rotated by 1.8 degrees. For a full rotation such a motor therefore needs 200 fullsteps. With modern boards (like the StepRocker) a fullstep can be devided into a certain number of microsteps. The Steprocker allows 256 microstpes for one fullstep. Other boards use probably a different number of microsteps for one fullstep ( e. g. only 16 microsteps). When designing the transport script you have to keep that in mind.
Number of start image
The grabbed frames are stored on a (permanent) storage media (hard disk or equivalent). Therefore a special directory structure has to be established. In the base directory the project directories are allocated. A project directory contains at least a "FRAMES" subdirectory. It also hosts the project parameter repository "INIProjFile.txt".
The "FRAMES" directory of a project again can be devided into several subdirectories in order to keep the number of images stored in such an image subdirectory reasonably small. Within an image subdirectory the image number must start with 0 (that is due to a restriction of VirtualDub and AviSynth). As it is very likely, that the full number of images composing a film cannot be grabbed in a single session, it must be possible to set a start number for a session. This start number can be automatically evaluated as the next free image number in an image subfolder. This is done by clicking the Find button which places the next free number in the start number field.
If you want to replace existing images in an image subfolder, you can set an individual start number. It is not checked if images are overwritten.
Frame count
With the frame count you can limit the session to grab only a certain number of images. The grabbing process is stopped, when the frame count is reached.
Transport N frames
With this values you can advance the movie by a certain number of frames without storing the images. The field designated "N=" sets the number of frames to be skipped, the button "start transport" starts the tranportation and with button "stop transport" you can interrupt an ongoing transportation.

The Video Device Parameter Pane

The video device parameter pane contains the input fields and buttons to describe the required parameters and actions for the frame grabbing.

Field names and field functions

find video device and camera resolution
Clicking the "find video device" button opens the dialog to list the attached video capture devices from which you can select the desired video device.
Normally available camera (video) resolutions are:
1. 640 x 480
2. 800 x 600
3. 1280 x 960
4. 1600 x 1200
5. 2048 x 1530

The Accord .NET modules which are used to get the video frames do not support snapshot catching. Therefore only video frame grabbing is supported.



Via this dialog you select the appropriate video capture device and the desired camera resolution you want to use for the grabbed frames.
The selected device and the selected camera resolution is shown in the video device parameter pane.
For S8 (Super 8 - Single 8) movies a camera resolution of 800x600 or 1280 x 960 is normally very good choice.





Target video resolution
Via this drop down list field the desired video image dimensions can be selected to which the grabbed images finally can be resized.
Available video target resolutions are:
1. 640 x 480 NTSC
2. 768 x 576 PAL SD
3. 960 x 720 PAL 720P
4. 1440 x 1080 Full HD
5. 2880 x 2160 4K
Additional grabbing contol parameters

To control the frame grabbing there are some additional parameters provided. These parameters are: 

flip image - this allows to use frames of films which are captured upside down (that is emulsion at top, sprockets right of the film strip in moving direction in the capturing device).

pre-stabilize - this filed shows if pre stabilizing frames is performed. Pre stabilization can be done, if the images are grabbed with (at least a part of) the transportation hole(s) visible. By that a little bit of the area the Definer Window provides for the image gets lost, but the advantage is, that images are captured pretty stabil and do not jump up and down in the final video clip. This is especially advantageous if you use a sprocket wheel for transportation as sprocket wheels deliver only an accuracy of about 5% (about 35 pixels up or down for 720P clips) and that is to much for a video clip.

Garbage collection after number of frames grabbed
This allows to control, when to do a garbage collection. The number of frames between garbage collections is set here, although Windows does not strongly stick to this setting. It might happen, that garbage collections are done a little bit earlier or later. Garbage collections are performed, when the grabbing seems to make a short pause.

to the table of content

Buttons of the video device parameter pane

The panel has 4 buttons in the last row of the pane.

The buttons are:

1. find video device - already described above. See; find video device and camera resolution.

   You should select the target resolution before pressing this button, because as soon as the video device and the camera resolution is set, the video device ist automatically prepared (warmed up) and the frame definition dialog is started after a certain warming up time. If the colors of the image still seem not to be fully OK in t he upcoming frame definition pane, you should press the "c Img. position" button in the window. See later !

2. The button FrameDefinition  activates the "Frame Definition Dialog".
3. reset  -  this button resets the form to the default field contents as actually stored in the INI File..
4. exit -  by pressing ths button you leave the application, It is the same function as triggerd by the "File -> Exit" menu.

Preparing the frame (size and color) for grabbing

After the video capture device is started and warmed up, the frame size and color definition window is presented. It shows the first grabbed image as seen by the video catching device (the microscope).



If no image could be scanned (probably because the microscope is not switched on) a notification image appears that informs you about what might have happened. I also might help to adjust the brightness threshold (default value 220). This is the color at which the sprocket hole evaluation process decides, which pixels are considered to be bright or dark. A sprocket hole border is asumed if there is a significant change in the brightness of consecutive pixels.

Special care has been taken, if a sprocket wheel is used for transportation and if Pathé footage has to be scanned. 9.5 mm films have the sprocket hole in the middle of the film and not at the left border.
The left image shows the image position, that should be achieved as start position. The blue area is the definition window rectangle.
Due to the inaccuracy of the stepper motor it might happen, that the scanned images move up and down. Therefore the magnification should selected in such a way that 2 sprocket holes (or parts thereoff) allways will be visible .
You may see during scanning positions of the sprocket holes that are a combination of 2 red or a a red and a green hole as shown in the right image.

Similar things can happen for film types, where the sprocket holes are located at the left windows side but at the image separation line (16mm or N8 / R8).

If no pre-stabilisation is pssible (no sprocket hole visible or sprocket hole misplaced), it is sufficient to set the magnification in such a way, that no borders appear in the picture box.

With the microscope you adjust the focusing and the magnification. With the focusing rails you correct the image position ( up, down., left, right, eventually a rotation). If the result is acceptable, you can terminate the correction process and return to the definition dialog by pressing the button "stop image positioning" in the left lower corner of the window.

As we deal with very tiny position changes, this task is not easy.
You have to perform this process very accurately and it needs significant training to do the job with the required precission.

If you'r pleased with the image position, you have to set the extraction size. This is done by clicking the button "img. pos and size". You can set the desired section with the left and right mouse button.
First click with the left mouse button in the image at the position, the left upper corner of the final image should be. Two yellow lines show what has been selected.
Then click with the right mouse button in the image at the position, the right lower corner of the final image should be. Now a yellow rectangle defines the extraction area.
If yuo are not satisfied with this rectangle, you can repeat the selection by clicking the middle mouse button. The previous selection will be ignored.

The part of the image which will be caught is now shown in the "Define image extraction and image color correction" dialog by a yellow rectangle. If the area is not correctly as you want it, you can fine adjust this area via the numeric up and down fields.
6 values can be modified via these fields:

• the X position of the upper left corner of the result image
• the Y position of the upper left corner of the result image
• the desired width of the result image
• the desired height of the result image
• trim image width correction - useful for images which are not stabilized
• the image height correction - useful for images which are not stabilized

Control and monitor the image catching

As soon as the Start Recording button is pressed in the frame definition dialog

With the microscope you adjust the focusing and the magnification. With the focusing rails you correct the image position ( up, down., left, right, eventually a rotation). If the result is acceptable, you can terminate the correction process and return to the definition dialog by pressing the button "stop image positioning" in the left lower corner of the window.

Control and monitor the image catching

As soon as the Start Recording button is pressed in the frame definition dialog the "Image grabbing controller" window opens with the image as grabbed by the microscope as first image.

Pressing the "start" button will start the grabbing process. From this point in time the images are shown in the progress dialog in their final form as they will be stored in the target folder for video clip generation.(see right picture)

The dialog is invoked from the Start Recording button in the definition dialog.
It shows the the target directory into which the scanned frames are stored.
The second line shows the name of the image actually processed.
The third line shows the name of the last image to be captured, and it indicates, that the frames are retrieved from a video device ("V")

There are 3 buttons.

1. The left button has 3 functions:
   • start starts the grabbing process at the the beginning of the grabbing session .
   • pause interrupts a running grabbing process
   • continue continues an interrupted grabbing process.
   
   this button changes its label according to the process state. At the beginning it says START. If you click the button with the START label, the grabbing process is started and the label is changed to "pause" processing. When the process is interrupted, you can go to the definition window or the main window to make changes - eg. change the number of images still to be processd or change the image color.
2. The button "-> main window" transfers the control (for the mouse) to the main window and
3. the button "to define window" transfers the control (for the mouse) to the definition window

There are 2 check marks.

1. The checkmark "color adjustment" triggers color adjustment for the grabbed images according to the settings in the definition window. If the button is not clicked, no color adjustment is performed.
2. The checkmark "shutdown" tell the program, that the computer should be powered off after the grabbing session has finished. This is usefull for unattended over nicht sessions.

In the main window a progress report is given, which shows, how many frames per minute are grabbed and an estimate, when the grabbing session might be completed.
In the message area also sometimes a message shows up, that notifies the observer, that the operating system has performed a garbage collection. This is to explain, why sometimes the frame grabbing seems to pause unintetionally.

Last change: June 21, 2020 WK