The other day, I posted some static images (no movement) from the A329T camera. That was pretty impressive, but only part of the story. Today, I made some additional footage and made some screen shots of individual frames from the MP4 files. I used CapCut to examine the video file, zoom in, and make screen grabs.
The overall scene is that I'm sitting in a turn lane with a red light and traffic is moving past in the lanes to my right at 35-40mph. Here is the overall scene from the 4k main camera, grabbed from VLC player. As you can see in the stamps at the bottom of the frame, HDR is enabled for both the front and telephoto cameras (I forgot to turn it off after making the comparisons that I posted previously - doh!).
Then I used CapCut to advance, frame by frame, until the back left wheel of the ambulance was aligned with the second white stripe from the crosswalk (I don't have this same granularity with VLC, so the image above doesn't quite show the ambulance wheels on the second line of the crosswalk). With CapCut, I zoomed in to 250% and focused on just the license plate. The resulting image is a little fuzzy, but clearly readable:
Then, I advanced the video by 5 frames (ambulance is now further away) to have another look. The image is a pinch smaller, but even more easily readable. I presume the additional clarity is derived from less right-to-left movement on a frame-to-frame basis as the ambulance moves further away from my stationary car. Impressive that the plate rendering got CLEANER with increased distance from my car, even though the image area itself is SMALLER... Very nice. I should probably repeat this set of images and zooms with HDR turned off and see how that impacts the clarity of the resulting images. That would be an interesting comparison and provide some additional insights about using HDR (or not) during the day with moving targets.
The plate grabs above were going by at about 35-40 mph. I also zoomed in (250 percent) on two other areas in the frame that were stationary for a closer look. The first is the electronic sign at the gas station. The Sunoco logo at the top is very clean and clear, as are the illuminated numbers for the price of gas.
Then I zoomed in (300 percent) on another sign on the left side of the road (directly in the center of the whole image I posted above) that was a bit further away along with an approaching car. Due to the greater distance, this sign and the approaching car are not quite so clean. This is perhaps beyond reasonable expectations to get a clean rendering, even from a 4k camera, due the the distance involved. The overall rendering of the sign, however, is pretty good - there is some ghosting along the perimeter of the sign and the outline of the adjacent roof in the left side of the image.
I then compared the footage from the 4k main camera (above) to that of the 2k 4x telephoto front camera (below). Here is the entire frame as captured from VLC Player:
Because the telephoto lens was not able to see the crosswalk in the previous image, I instead advanced to the frame where the rear wheels of the ambulance were all of the way through the intersection, and then zoomed in (by 250 percent) again on the license plate. As expected, I found a nice, clear rending of a moving license plate from much farther away:
Interestingly, the ambulance plate remained quite readable even after the ambulance was well past the intersection. Here is a 100% zoom/crop of the point at which the plate starts to become harder to read with the telephoto camera. Two or three more frames more renders the plate unreadable. That's a pretty good distance at a 35-40 mph speed differential!
The telephoto lens was also unable to capture the gas station sign for a direct comparison (the telephoto factor placed it outside of the frame), so I zoomed in (also 250 percent) on the same road sign as above that is further away. This zoom, too, exhibits great clarity as I expected (this is a static image - my car is not moving). This is a pretty impressive image when compared to the very first image in this post that comes from the main camera.
Overall, this is pretty impressive plate capture given the 35-40 speed differential my of stationary car with the traffic passing by on the right. Still images are equally impressive.
In another few days, my plan is to post some screen grabs from the highway where both cars (mine and target car) will be in motion. I will also make sure that HDR is returned to "timer" mode so it off during the day instead of just being set to "on." I also want to post some screen captures from the extensive set of menus in the A329T. It's quite a lot to learn
😉
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