Workflow Faces Similarity in HGrid247-3.5
Purpose
This workflow is used to:
- Calculating the level of facial similarity
- Identify whether two images contain the same person
- Sort results by highest facial similarity
In contrast to ordinary image similarity , here the focus is only on the facial area (face region) .
Concept Face Similarity
The main process consists of 3 stages:
- Face Detection → detects faces in images
- Feature Extraction → extracting facial features
- Similarity Matching → comparing faces
Step 1 – Copy Workflow
From the previous workflow:
WFImageSimilarity
Copy to:
WFFaceSimilarity
Purpose:
- reuse pipeline
- just replace the similarity method
Step 2 – Transformator_2 Modification
On Transformator_2 :
Delete function:
ImageSimilarity

Because it will be replaced with a special one for the face
Step 3 – Adding FaceSimilarity
Add function:
FaceSimilarity
Input-output relationship:
image1 ─┐
├── FaceSimilarity ──> similarity
image2 ─┘
Important Parameters
1. Face Detector
CLMFaceDetector
Function:
- detecting face position in an image
- ensure that only the facial area is processed
2. Facial Feature Extractor
DoGSIFTFeature
Function:
- extract important facial features
- such as eyes, nose, mouth
3. Key Point Descriptor
SIFT
Function:
-
compare facial features between images
Step 4 – Compile Workflow
Click the button:
Generate (
)
Output:
workshop_mr.jar
Step 5 – Running on Hadoop
Run on an Apache Hadoop cluster :
hadoop jar workshop_mr.jar workshop.WFFaceSimilarity photo output_fsim photo/photo1.jpg
Parameter
Parameter Description
------------------------------------
photo facial image dataset
output_fsim results folder
photo1.jpg reference face
Sample Output
photo/photo1.jpg photo/photo1.jpg 1.0
photo/photo1.jpg photo/photo5.jpg 0.7046571656156865
photo/photo1.jpg photo/photo7.JPG 0.6650472587046466
photo/photo1.jpg photo/photo2.jpg 0.3304030217553085
photo/photo1.jpg photo/photo4.jpg 0.3246716833058123
photo/photo1.jpg photo/photo3.jpg 0.3175215036337799
photo/photo1.jpg photo/photo6.jpg 0.032529146286689375
Interpretation of Results
Similarity Value Meaning
-----------------------------------------
1.0 identical faces
> 0.7 very similar
0.3 – 0.7 quite similar
< 0.1 not similar
Note : The file of workflow WFFaceSimilarity can be found in the following link :
WFFaceSimilarity.csd