Framebuffer-less system and method of convolutional neural network

1. A framebuffer-less system of convolutional neural network (CNN), comprising:

a region of interest (ROI) unit that extracts features, according to which a region of interest in an input image frame is generated;

a convolutional neural network (CNN) unit that processes the region of interest of the input image frame to detect an object;

a tracking unit that compares features extracted at different times, according to which the CNN unit selectively processes the input image frame; and

a temporary storage for storing the features extracted by the ROI unit;

wherein the ROI unit adopts scan-line based technique and block-based scheme to find the region of interest in the input image frame, which is divided into a plurality of blocks of image;

wherein the ROI unit comprises:

a feature extractor that extracts the features from the input image frame; and

a classifier that makes decision whether to perform CNN for each block of image, thus generating a decision map, according to which the region of interest is determined.

2. The system of claim 1 , wherein the ROI unit generates block-based features, according to which decision of whether to perform CNN is made for each block of image.

3. The system of claim 1 , wherein the feature extractor generates shallow features of the blocks of image according to block-based histogram or frequency analysis.

4. The system of claim 1 , wherein the temporary storage comprises a first feature map storing features of a previous image frame, and a second feature map storing features of a current image frame.

5. The system of claim 4 , wherein the tracking unit compares the first feature and the second feature map, and accordingly updates the decision map.

6. The system of claim 1 , wherein the temporary storage comprises a sliding window storing a block of the input image frame.

7. The system of claim 1 , wherein the CNN unit comprises:

a convolutional unit including a plurality of convolution engines to perform convolution operation on the region of interest;

an activation unit that performs activation function when predefined features are detected; and

a pooling unit that performs down-sampling on the input image frame.

8. A framebuffer-less method of convolutional neural network (CNN), comprising:

extracting features to generate a region of interest (ROI) in an input image frame;

performing convolutional neural network (CNN) on the region of interest of the input image frame to detect an object; and

comparing features extracted at different times and accordingly processing the input image frame selectively;

wherein the ROI is generated by adopting scan-line based technique and block-based scheme, the input image frame being divided into a plurality of blocks of image;

wherein the step of generating the ROI comprises:

extracting the features from the input image frame; and

making decision by classification whether to perform CNN for each block of image, thus generating a decision map, according to which the region of interest is determined.

9. The method of claim 8 , wherein the step of generating the ROI comprises:

generating block-based features, according to which decision of whether to perform CNN is made for each block of image.

10. The method of claim 8 , wherein the step of extracting the features comprises:

generating shallow features of the blocks of image according to block-based histogram or frequency analysis.

11. The method of claim 8 , further comprising a step of temporarily storing the features that generates the ROI.

12. The method of claim 11 , wherein the step of temporarily storing the features comprises:

generating a first feature map storing features of a previous image frame; and

generating a second feature map storing features of a current image frame.

13. The method of claim 12 , wherein the step of comparing the features comprises:

comparing the first feature and the second feature map, and accordingly updating the decision map.

14. The method of claim 11 , wherein the step of temporarily storing the features comprises:

generating a sliding window storing a block of the input image frame.

15. The method of claim 8 , wherein the step of performing convolutional neural network (CNN) comprises:

using a plurality of convolution engines to perform convolution operation on the region of interest;

performing activation function when predefined features are detected; and

performing down-sampling on the input image frame.