How to Enhance Low Quality CCTV Footage of a License Plate with MotionDSP Forensic

Summary

This video tutorial demonstrates techniques for enhancing a license plate in a surveillance video for forensic analysis. It guides viewers through zooming in, setting a region of interest, and applying resolution filters with super resolution and fusion parameters. The process includes adjusting contrast and sharpening tools, and experimenting with detail mode for clarity. The tutorial concludes with creating snapshots of the enhanced license plate and saving them.

Takeaways

• 🔍 The process begins by zooming in on the license plate area for enhancement.
• 🛠 The 'region of interest' tool is activated to isolate the license plate for focused enhancement.
• 🖼 Resizing the region of interest box ensures only the license plate is enhanced, avoiding other areas.
• 🔧 The resolution filter is used, sampling up to 51 frames and applying a super resolution factor.
• 📈 Upscaling to the maximum value improves the clarity of the license plate characters significantly.
• ⚙️ Additional parameters like the fusion and accuracy settings are adjusted for further refinement.
• ✨ Applying the contrast filter helps darken the characters and make them stand out from the background.
• 🛠 The sharpening tool is employed, along with the deep learning tool, to further enhance the license plate details.
• 🧐 Testing with the detail mode shows that it can add more clarity but may distort some areas.
• 📸 Final snapshots are taken with and without the detail mode enabled, and the images are saved.

Q & A

What is the first step in enhancing the license plate in this process?

The first step is to zoom in on the area of interest, which in this case is the license plate on the back of the vehicle.

How is the region of interest (ROI) tool activated?

The region of interest (ROI) tool can be activated through the 'mouths tools' or by clicking on the region of interest filter.

Why is the region of interest (ROI) tool used?

The ROI tool is used to focus on enhancing a specific area, such as the license plate, while excluding irrelevant parts like the ground.

What does the resolution filter do?

The resolution filter helps enhance the image by sampling surrounding frames and upscaling the selected area, making details clearer.

How many frames are sampled when using the resolution filter in this example?

The maximum number of frames sampled in this example is 51.

What is the effect of applying the fusion parameter in the resolution filter?

The fusion parameter, when maximized, further enhances the clarity of the details on the license plate.

How does the contrast filter help in this enhancement process?

The contrast filter helps darken the characters on the license plate and make them stand out against the background.

What additional tool is applied after the contrast filter?

After the contrast filter, the sharpening tool is applied to further enhance the details of the license plate.

What is the effect of using the detail mode?

Detail mode helps bring out more fine details in the characters on the license plate, though it may slightly distort other parts of the image.

How are snapshots created and saved after enhancing the license plate?

Snapshots are created by right-clicking and selecting 'save as' for each enhanced image, specifying a save location for the files.

Outlines

00:00

🔍 Enhancing License Plate Visibility

This paragraph discusses a method for enhancing a license plate in a video for forensic analysis. The process begins by zooming in on the license plate and using the 'Region of Interest' tool to focus enhancement on that area. The resolution filter is then applied with a high frame sampling rate and a maximum super resolution factor to sharpen the image. Additional parameters like fusion and accuracy are adjusted to bring out the details of the characters on the plate. The contrast is increased to make the characters stand out against the background, and a sharpening tool is used to further enhance clarity. The 'Detail Mode' is considered for additional enhancement, and snapshots are taken with and without this mode enabled for comparison.

Keywords

💡License Plate

A license plate is a metal or plastic plate attached to a vehicle or vessel that displays a unique identifier, usually assigned by a government authority. In the video, enhancing the license plate's visibility is the primary goal, as it is crucial for forensic analysis and identifying vehicles in surveillance footage.

💡Region of Interest (ROI)

Region of Interest is a term used in image processing to define a specific area within an image that is of particular interest for analysis or enhancement. In the video, the ROI tool is used to focus on the license plate, ignoring other parts of the video that are not relevant to the enhancement process.

💡Resolution Filter

The resolution filter is a tool used to increase the clarity of an image by manipulating the number of pixels. In the video, the resolution filter is applied to the license plate to enhance its details by increasing the number of surrounding frames sampled and upscaling the image.

💡Super Resolution

Super resolution is a method in image processing that increases the resolution of an image beyond the limit of the original image capture device. In the script, super resolution is used to upscale the image of the license plate to its maximum value to make the characters more readable.

💡Fusion Parameter

The fusion parameter in image processing refers to the blending of multiple images or frames to create a single image with improved quality. In the video, the fusion parameter is maximized to enhance the details of the license plate characters.

💡Accuracy Setting

Accuracy setting in the context of image processing refers to the level of precision applied to an enhancement algorithm. The script mentions adjusting the accuracy setting to exaggerate the details of the license plate characters, which helps in making them more distinct.

💡Detail Mode

Detail mode is a feature that emphasizes the fine details within an image. The video discusses toggling detail mode on and off to see if it improves the clarity of the license plate characters, suggesting that it does add more detail at the cost of some image distortion.

💡Contrast Filter

A contrast filter is used to adjust the difference between the light and dark areas of an image, making the subject stand out more. In the video, the contrast filter is applied to darken the characters on the license plate, making them more distinct against the background.

💡Sharpening Tool

The sharpening tool is an image processing technique that enhances edges within an image, making them appear clearer and more defined. The script mentions using a sharpening tool to improve the visibility of the license plate characters.

💡Deep Learning

Deep learning refers to a subset of machine learning that uses artificial neural networks to model complex patterns in data. In the video, deep learning is mentioned in the context of enhancing the image, suggesting that an AI-based approach is used to improve the image quality.

💡Snapshot

A snapshot in this context refers to a saved image or frame captured at a specific moment. The video script describes taking snapshots of the enhanced license plate with and without detail mode enabled, to compare the effectiveness of different enhancement techniques.

Highlights

Zoom in on the license plate for enhancement, focusing on the area of interest.

Enable the region of interest tool to target the license plate area.

Resize the region of interest box to only enhance the license plate, avoiding irrelevant parts like the ground.

Activate the resolution filter, which samples surrounding frames for better clarity.

Max out the sampling frames to 51 for better clarity and precision in the image.

Upscale the license plate using the super resolution factor to the maximum value.

Apply the fusion parameter and max it out to enhance the clarity of the license plate further.

Utilize the accuracy setting to refine the details, particularly around the edges of the characters on the plate.

Apply a contrast filter with default values to darken characters and make them more distinct.

Use the light color option to make the license plate characters stand out more from the background.

Apply the sharpening tool to further enhance the details of the license plate.

Use a deep learning tool to improve the overall enhancement of the image.

Test the detail mode to enhance the characters on the plate further while distorting other parts of the image slightly.

Take snapshots of the enhanced image, one with and one without detail mode enabled.

Save the final enhanced images by right-clicking and selecting 'save as' to specify the location.

Transcripts

in this next example we're going to look

at some methods for enhancing a license

plate in the canter forensic and so

first we're going to start by zooming in

on the area that we want to enhance in

this case it's going to be the license

plate on the back of the vehicle and

then the first thing we want to do is we

want to enable our region of interest

tool which we can do over here in our

mouths tools or by clicking on the

region of interest filter and then

select that tool so we can resize this

box bring it over to the area that we

want to enhance resize it accordingly

and so now what we're doing is we're

only going to be enhancing this area

within our region interest box since we

don't care about enhancing other things

in the video like the ground we may be

interested in enhancing other parts of

the vehicle later but for now we're just

going to focus on the license plates we

had drawn our region of interest

accordingly and we're going to start by

enabling our resolution filter there's a

much longer explanation for our

resolution filter works and some of our

other demo videos I will rehash that

here but basically we're going to start

by looking at the number of surrounding

frames that were sampling you can see

I'm just going to go ahead and max that

out at 51 frames and then we're going to

upscale using our super resolution

factor we're going to upscale it all the

way to the maximum value for and you can

see already we're starting to get a much

clearer picture of the characters on

this license by effect you can probably

almost read it now we're going to apply

some additional parameters within the

resolution filter go ahead and fire

fusion parameter go ahead and max that

out and we're going to apply our

accuracy setting and you can see we go

all the way over kind of exaggerated

some of these things but here we can

kind of see some of the detail edges

these characters a little bit more you

know kind of distorts other parts of the

age and then we might want to play with

using our detail mode once we apply some

other filters I'm gonna leave that

turned off for now next we're going to

start with our contrast filter and we're

going to just for the most what we're

going to use default values we shouldn't

have to make too many adjustments with

this example we'll start with our

contrast setting kind of darkens those

characters a little bit more on light

color is going to do the same it's going

to make it really stand out from the

background the license plate will apply

our sharpening tool and try with our

deep learn to all that kind of so that

helps a little bit as well and so now we

want to look at a see if our detail mode

will kind of help in this case and I

think it actually does in this case

going to bring them a little bit more

detail you know kind of distort some

other parts of the image so what we'll

do now that we have got a pretty pretty

good enhancement of this license plate

again just using a couple of simple

clicks a couple of filters without

adjusting we'll just do some default

settings we're going to create two

snapshots from this and we'll go ahead

and bring up our product list here we'll

go ahead and take a snapshot without the

detail mode enabled and we'll take a

snapshot with the detail mode enabled

and that's pretty much it and now all we

have to do is just right click and hit

save as for each of these images and

specify save location and we're done