2. What is Emotion?
Emotions are reflected in voice, hand and body gestures,
and mainly through facial expressions.
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3. Facial Emotion
There are six types of facial emotions.
Anger Fear Disgust Happy Sad Surprise
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4. Importance of emotion recognition
Human beings express emotions in day to day
interactions.
Understanding emotions and knowing how to react to
people’s expressions greatly enriches the interaction.
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5. Review Of Previous Work
Image pre-processing
Facial feature extraction
-select some point on feature region
-consider a matrix surrounding that point
-calculate distances
Facial expression detection
Reff.: [“Optical flow based analyses to detect emotion from human facial image data”- Axel Besinger ,
Tamara Sztynda, Sara Lal , Carmen Duthoit, Johnson Agbinya, Budi Jap ,David Eager, Gamini
Dissanayake]
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8. Capture Image
Digital camera, web-cam
Resolution must be fixed
Distance between the web-cam and the face has to be
fixed.
Position of face must be fixed
Must not wear glasses or have facial hair.
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9. Capture I age Co t…
Normal Facial Image Emotional Facial Image
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10. RGB to gray scale conversion
Color Facial Image Grayscale Facial Image
Reduce complexity.
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11. Scale Normalization
Select only the face portion within a rectangular
frame
Remove unnecessary information
By defining region.
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12. Crop Feature Regions
Region of Interest: two Eyes, two Eye brows, Lip
By defining the particular regions.
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14. Algorithm:
Input: A Sample Image
Output: Detected Edges
Step 1: Accept the input image
Step 2: Apply mask h1 and h3 (prewitt mask) to the input
image.
Step 3: Masks manipulation of h1 and h3 separately on
the input image
Edge Detection Co t…
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15. Edge detectio Co t…
Step 4: Results combined to find the absolute magnitude of the
gradient
Where
Step 5: The absolute magnitude is the output edges.
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16. Facial Emotion Classification
Calculate displacement of the points.
Calculate averages of those values.
Calculate standard deviation (SD) of those averages.
Compare this SD with a threshold.
Get Emotion.
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17. Algorithm
Step 1: Take a still image of a normal expression pic1
(say) of a human face.
Step 2: Converts the color image to grayscale.
Step 3: Crop the five facial image region of interest (ROI)
(eyes, eye brows and lip) from the image by defining
region.
Step 4: Find edges of all image region.
Step 5: Take a still image of a emotional face (angry or
happy) pic2 (say) of same person and repeat step 2, 3
and 4.
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18. Algorith Co t…
Step 7: Comparing the deviation of edges of the
specified region of pic1 with pic2 by finding the
Euclidian distances of coordinate of each pixel.
Step 8: Put the Euclidian distances in a array k (say).
Step 9: Find the standard deviation (SD) from the
elements of array.
Step 10: Comparing the SD with pre-define threshold
and get the emotions.
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19. Experiment & Result
30 images were used to create the template.
60 were tested.
Statistical Values of Three categories
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23. Conclusion and Future Work
Implementation through this process is quite easy.
Have to improve over the capturing Process.
ROI extracted manually
-That should be automatically.
Edge detection procedure should be less complex.
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