Effect of Tracker Radius on Accuracy and Speed

The beads used for these tests are generated algorithmically. They are a mixture of dark-on-gray discs of radius 3 and dark-on-gray Gaussian spots of standard deviation 3. The tracker radius for the disc varies. The background intensity in each image is 75% of maximum brightness and the darkest spot on the disc or the Gaussian is 25%. There is noise with a mean of 2000 and a variance of 1e7 added in these images. The disc samples are averaged over a uniform grid that has 100 times the resolution in X and Y of the final image. The Gaussians are averaged over a uniform grid that has 10 times the resolution in X and Y. This should make it possible to precisely localize the spots to 1/100th of a pixel (if there were no image noise). For all trials, the Video Spot Tracker precision setting is 0.001 and sample_spacing is 0.4.

Test 1: Disc spots

Radius	Bead Type	Motion	Mean Radial Error	Mean X Error	Mean Y Error	Max Radial Error	X Bias	Y Bias	Estimates/Sec	True Log	VST Log	Images
7	Disc	Circular	0.0486907	0.0344031	0.0280201	0.115622	0.00951916	0.00296153	46.9673	Log	VST Log	Images
9	Disc	Circular	0.0494894	0.0346144	0.0290377	0.116782	0.00923431	0.00258722	45.3433	Log	VST Log	Images
11	Disc	Circular	0.050164	0.0355769	0.0286389	0.124937	0.00964936	0.00192797	47.305	Log	VST Log	Images
13	Disc	Circular	0.0499521	0.0350477	0.0293512	0.109133	0.00969821	0.0035963	35.2955	Log	VST Log	Images
15	Disc	Circular	0.0510675	0.0360346	0.02948	0.111003	0.0103492	0.00270109	28.6239	Log	VST Log	Images
17	Disc	Circular	0.050311	0.0345164	0.0303385	0.115678	0.0101702	0.00279072	23.3485	Log	VST Log	Images

Example images follow:

disc_3_sym_circle.0000.bmp

Test 2: Gaussian spots

Radius	Bead Type	Motion	Mean Radial Error	Mean X Error	Mean Y Error	Max Radial Error	X Bias	Y Bias	Estimates/Sec	True Log	VST Log	Images
7	Gaussian	Circular	0.097123	0.0626051	0.0612745	0.274349	0.00247977	0.0175368	49.9561	Log	VST Log	Images
9	Gaussian	Circular	0.103187	0.0655755	0.0661421	0.271476	0.00090105	0.0153313	58.7816	Log	VST Log	Images
11	Gaussian	Circular	0.101721	0.0676506	0.0634217	0.279892	0.00128347	0.013248	51.2662	Log	VST Log	Images
13	Gaussian	Circular	0.10535	0.0670564	0.0671937	0.266307	4.6475e-005	0.0168287	39.7679	Log	VST Log	Images
15	Gaussian	Circular	0.109105	0.0709823	0.0684932	0.290063	0.00281347	0.0167067	30.6581	Log	VST Log	Images
17	Gaussian	Circular	0.11093	0.0711371	0.0717132	0.275523	0.00402596	0.0176751	24.7892	Log	VST Log	Images

Example images follow:

gaussian_10_sym_circle.0_0.0000.bmp