Search found 97 matches

by kwiley
Fri May 17, 2019 9:45 am
Forum: General Topics
Topic: Global Shutter
Replies: 30
Views: 9937

Re: Global Shutter

On the whole color debate above, one very application-specific approach would be to record Bayer filter data (i.e., raw sensor data) straight onto the SD card, such that it could be deBayered and processed at a later time. In such a way, one could use a global shutter to record high framerate color ...
by kwiley
Wed May 15, 2019 9:32 pm
Forum: General Topics
Topic: IDE v4.0 vs 2.2.0?
Replies: 5
Views: 210

Re: IDE v4.0 vs 2.2.0?

Ah, I see. It's some cross-platform wrapper around QT. I'm not familiar with that approach to application design. I should really try to jump in here at some point to see if I can help out some.
by kwiley
Wed May 15, 2019 9:29 pm
Forum: General Topics
Topic: IDE v4.0 vs 2.2.0?
Replies: 5
Views: 210

Re: IDE v4.0 vs 2.2.0?

Well, it's built into the app. The Finder pulls that information from a Mac application's package assets. I haven't dived into the source for either the camera or the IDE yet, but I can take a look at it when I get a chance. How is the IDE written? I presume it is a native Cocoa application, right? ...
by kwiley
Wed May 15, 2019 2:56 am
Forum: General Topics
Topic: IDE v4.0 vs 2.2.0?
Replies: 5
Views: 210

Re: IDE v4.0 vs 2.2.0?

If you Get Info on the application, it says v4.0. I just noticed that if I go ahead and run it anyway, the app says it's v2.2.0 in the About box. So, it's just the Info box from the Finder that shows 4.
by kwiley
Wed May 15, 2019 1:34 am
Forum: General Topics
Topic: IDE v4.0 vs 2.2.0?
Replies: 5
Views: 210

IDE v4.0 vs 2.2.0?

The IDE on my Mac from Dec. 2018 is v4.0, but the version available for download is v2.2.0, although surely far more recent. This isn't very important, but may I ask the rationale behind the version numbering for the IDE?
by kwiley
Wed May 15, 2019 1:17 am
Forum: General Topics
Topic: H7 male vs female headers
Replies: 2
Views: 81

Re: H7 male vs female headers

Ha. Okay, I understand. I'm happy to do it the right way. I just wanted to check before I started soldering. It makes particular sense for me to do it that way since I intend to mount the M7 and H7 next to one another, so it will be easier if they are configured the same way.

Cheers!
by kwiley
Wed May 15, 2019 12:18 am
Forum: General Topics
Topic: H7 male vs female headers
Replies: 2
Views: 81

H7 male vs female headers

My H7 and global shutter have arrived. Woo hoo! I see the H7 doesn't come with the headers presoldered, and in fact comes with both a set of one-sided-male and two-sided-male-female headers. The M7 I already have came with the two-sided headers only, and presoldered at that with female pointing out ...
by kwiley
Sun May 05, 2019 2:01 am
Forum: General Topics
Topic: Global Shutter
Replies: 30
Views: 9937

Re: Global Shutter

I'm familiar with the exposure trade off and gamma corrective measures. I was experimenting with a 3500 fps camera recently. Thanks.
by kwiley
Sun May 05, 2019 12:11 am
Forum: General Topics
Topic: Global Shutter
Replies: 30
Views: 9937

Re: Global Shutter

I'm looking forward to the imminent arrival of my H7 and global shutter. Color is not at all important to me (well, that's overstating it -- given unlimited resources, I would happily *accept* color, haha). My question is about the theoretical 200fps framerate. Do the higher framerates require downs...
by kwiley
Thu Mar 28, 2019 3:21 pm
Forum: Technical Discussion
Topic: Servo controllers: shield vs. PCA9685
Replies: 2
Views: 3638

Re: Servo controllers: shield vs. PCA9685

Thanks. That's what I expected.
by kwiley
Wed Mar 27, 2019 11:28 pm
Forum: Technical Discussion
Topic: Servo controllers: shield vs. PCA9685
Replies: 2
Views: 3638

Servo controllers: shield vs. PCA9685

I'm curious if there are any technical differences between the servo shield and the PCA9685, found many places online, such as (chosen for no particular reason) https://www.amazon.com/HiLetgo-PCA9685-Channel-12-Bit-Arduino/dp/B01D1D0CX2 . The shield fits nicely onto the OpenMV board profile, and tha...
by kwiley
Wed Mar 27, 2019 8:47 pm
Forum: Technical Discussion
Topic: 5V TTL?
Replies: 2
Views: 2492

Re: 5V TTL?

Yes, I noticed the comment about the ADC/DAC line, but serial comms would be over the UART lines. I take your point though. Thanks.
by kwiley
Wed Mar 27, 2019 6:06 pm
Forum: Technical Discussion
Topic: 5V TTL?
Replies: 2
Views: 2492

5V TTL?

I see that OpenMV is described as 5V tolerant but 3.3V nominal. Since TTL detects high voltage as anything above 2V, does this imply that OpenMV should communicate over serial just fine in both directions with a 5V device? Assuming the messages would actually get through in both directions (I'm mild...
by kwiley
Wed Mar 27, 2019 5:13 pm
Forum: Technical Discussion
Topic: LCD shield compatibility with servo and P&T shields
Replies: 2
Views: 2691

LCD shield compatibility with servo and P&T shields

If I'm understanding the pinouts correctly, the LCD shield should work with the servo shield, which relies exclusively on the I2C pins P4 and P5, but not the pan & tilt shield, which utilizes the servo pins P7, P8, and P9, which would double up on the LCD's use of P7 and P8, right? As a follow-up, w...
by kwiley
Thu Feb 14, 2019 1:12 pm
Forum: General Topics
Topic: exposure and gain control
Replies: 11
Views: 2782

Re: exposure and gain control

Are we able to achieve a relatively flat gamma curve? Flat gamma, while often not pleasing to the eye, is very helpful in analysis.
by kwiley
Tue Feb 12, 2019 7:50 pm
Forum: General Topics
Topic: exposure and gain control
Replies: 11
Views: 2782

Re: exposure and gain control

I already inquired about adding a global shutter module to my H7 preorder. I hope it all goes smoothly. :-) My initial project with the M7 has gone well, but I need more juice.
by kwiley
Tue Feb 12, 2019 2:05 pm
Forum: General Topics
Topic: exposure and gain control
Replies: 11
Views: 2782

Re: exposure and gain control

I used to do long exposure astrophotography with modified webcams. We (the group that was into this) would perform circuit modifications of the webcam to enable manual control of the sensor shutter and then we could run very long exposures. I wrote pretty much the only and best (if I may say so) Mac...
by kwiley
Sun Feb 10, 2019 5:11 pm
Forum: Technical Discussion
Topic: OSError: [Errno 110] ETIMEDOUT?
Replies: 3
Views: 2751

Re: OSError: [Errno 110] ETIMEDOUT?

Yeah, I did that, and if it solves the problem, that's fine. I was just curious what causes it and whether it indicates that I'm doing something wrong or can otherwise alleviate it.
by kwiley
Sun Feb 10, 2019 3:20 am
Forum: Technical Discussion
Topic: OSError: [Errno 110] ETIMEDOUT?
Replies: 3
Views: 2751

OSError: [Errno 110] ETIMEDOUT?

I occasionally get "OSError: [Errno 110] ETIMEDOUT" when querying a Sparkfun Qwiic keyapad (https://www.sparkfun.com/products/14836). It doesn't correlate with whether a button has actually been pressed. The error is merely associated with querying the line. Any thoughts?
by kwiley
Sat Feb 02, 2019 12:22 pm
Forum: Technical Discussion
Topic: Memory differences between terminal and IDE
Replies: 5
Views: 474

Re: Memory differences between terminal and IDE

Ah, mine's already tighter than that. It reduces variable names, replaces constants, etc. Okay, no worries.
by kwiley
Sat Feb 02, 2019 12:09 am
Forum: Technical Discussion
Topic: Memory differences between terminal and IDE
Replies: 5
Views: 474

Re: Memory differences between terminal and IDE

I've written my own basic code minimizer already, but did you have a specific tool in mind?
by kwiley
Fri Feb 01, 2019 9:52 pm
Forum: Technical Discussion
Topic: Memory differences between terminal and IDE
Replies: 5
Views: 474

Re: Memory differences between terminal and IDE

Well, I guess it works if I pull those imports into a new blank file. So the length of the file is part of the problem. I guess it tries to put the file in memory before processing the imports or something like that. Does that sound right?
by kwiley
Fri Feb 01, 2019 9:46 pm
Forum: Technical Discussion
Topic: Memory differences between terminal and IDE
Replies: 5
Views: 474

Memory differences between terminal and IDE

When I run my program from the IDE, it currently runs out of memory while pulling in the imports, before actually doing any work, so to speak. Admittedly, I pull in some modules that I wrote, not just "stdlib" like stuff. But if I copy/paste those exact initial import statements into a screen sessio...
by kwiley
Fri Feb 01, 2019 7:29 pm
Forum: Technical Discussion
Topic: External SD card access
Replies: 5
Views: 484

Re: External SD card access

Never a feature request, always an inquiry to current capabilities that I'm unsure I'm aware of. No worries.
by kwiley
Fri Feb 01, 2019 5:43 pm
Forum: Technical Discussion
Topic: uos vs os modules
Replies: 2
Views: 681

uos vs os modules

How does the uos module differ from the more standard os module? Should I be using one over the other if I want to read/write arbitrary files (not necessarily images, gifs, or videos) to and from the SD card?

Same question applies to the uio and io modules of course.
by kwiley
Fri Feb 01, 2019 5:40 pm
Forum: Technical Discussion
Topic: External SD card access
Replies: 5
Views: 484

External SD card access

I realize OpenMV provides its own SD card, but sometimes you want to utilize an external SD card. For example, I'm working with an Arduino shield that has its own SD card. In Arduinoland, it is accessed from the Arduino SD.h library, which uses SPI to interact with the SD card. There is an SS pin on...
by kwiley
Fri Feb 01, 2019 5:35 pm
Forum: Technical Discussion
Topic: Overclocking example seems out of date
Replies: 1
Views: 266

Overclocking example seems out of date

The overclocking example calls get_frequency() but the current options appear to be: >>> import cpufreq >>> cpufreq. __class__ __name__ set_frequency get_current_frequencies get_supported_frequencies >>> cpufreq.get_current_frequencies() (216, 216, 54, 108) >>> cpufreq.get_supported_frequencies() [1...
by kwiley
Tue Jan 29, 2019 1:12 pm
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

Ah, so even if I pass an image reference in to use as a preallocated buffer, I should still capture the returned reference and use that from that point forward.
by kwiley
Tue Jan 29, 2019 1:08 pm
Forum: Technical Discussion
Topic: gain maxes out at 32
Replies: 2
Views: 318

Re: gain maxes out at 32

Thanks. That's fine. Just wanted to understand what was going on.
by kwiley
Tue Jan 29, 2019 3:47 am
Forum: Technical Discussion
Topic: gain maxes out at 32
Replies: 2
Views: 318

gain maxes out at 32

The docs say you can set a gain ceiling up to 128, but if you print out the gain continuously, it never exceeds 32 (well, 29.82729, but that's the gain returned by get_gain_db() that corresponds to a setting of 32). Setting it to 64 or 128 doesn't push it up any higher. I tried setting the ceiling b...
by kwiley
Mon Jan 28, 2019 11:18 pm
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

So I'm attempting to preallocate an image to hold an extracted ROI from the sensor's snapshot. This seems to work: roi_img = sensor.alloc_extra_fb(roi_w, roi_h, sensor.RGB565) However, I have discovered that if I change the pixformat, the extracted ROI does not change with it even though it claims t...
by kwiley
Mon Jan 28, 2019 1:14 pm
Forum: Technical Discussion
Topic: M7 5V out?
Replies: 17
Views: 1587

Re: M7 5V out?

Out of curiosity, are you saying the diode in the same location on the H7 doesn't have an anode directly connected to 5V? I admit the H7 is a little more crowded so the diode isn't as easily exposed as I took advantage of (it looks like there is a resister just below it), but are you saying it is no...
by kwiley
Mon Jan 28, 2019 10:28 am
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

I don't think I realized I could keep multiple images in the frame buffer. I thought it *was* or *referred to* the image from the sensor such that any manipulations of the "frame buffer" altered that one "buffered most recent frame". I had misunderstood that entirely. I'll look into that option. It ...
by kwiley
Mon Jan 28, 2019 1:37 am
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

So, silly question. How do I create a blank Image of a given resolution and mode to pass into copy in the copy_to_fb parameter? I can visualize how to create a blank bytearray for raw pixel data and pass that in, but I don't see a way to create an Image. The only Image ctor I see in the docs creates...
by kwiley
Mon Jan 28, 2019 1:14 am
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

Can't wait to test drive it. Thanks.
by kwiley
Mon Jan 28, 2019 12:56 am
Forum: Technical Discussion
Topic: RGB channel extraction
Replies: 16
Views: 5648

Re: RGB channel extraction

Oh hey, look at that. You did. That's an awesome addition. It might be worth looking at the text quality a bit, at least to replicate the previous integer values (make 2 like the old 2) even if the floating values have some issues for the time being.

It's not too important.

Cheers!
by kwiley
Sun Jan 27, 2019 11:41 pm
Forum: Technical Discussion
Topic: RGB channel extraction
Replies: 16
Views: 5648

Re: RGB channel extraction

Ummm, funny question, but did you do anything to the fonts in the recent firmware? Drawn text looks quite different all of a sudden (and much worse, very hard to read now, at least at the same font settings).

I only see this new artifact at scale 2. Scales 1 and 3 look good.
by kwiley
Sun Jan 27, 2019 11:36 pm
Forum: Technical Discussion
Topic: RGB channel extraction
Replies: 16
Views: 5648

Re: RGB channel extraction

Oh, the "Run Bootloader" menu option seems to do the trick.
by kwiley
Sun Jan 27, 2019 11:15 pm
Forum: Technical Discussion
Topic: RGB channel extraction
Replies: 16
Views: 5648

Re: RGB channel extraction

May I presume this also includes the recent changes with regard to image rotation? Now I just have to learn how to flash the firmware. I see where the docs say "Use the IDE built-in dfu tool to update the firmware." but I haven't figured out what that means yet. I noticed that if I click the firmwar...
by kwiley
Sun Jan 27, 2019 12:08 pm
Forum: Technical Discussion
Topic: M7 5V out?
Replies: 17
Views: 1587

Re: M7 5V out?

If you have any thoughts at all on how to access the 5V on the H7, please let me know. I have access to a professional circuit-builder. He's...kinda incredible, so he can handle any soldering task I throw at him if there is even a merely schematic way to accomplish the hack. Of course, I suppose I c...
by kwiley
Sun Jan 27, 2019 12:04 pm
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

Ah, I did something similar on a PyBoard project, manually triggering the GC at optimal times. I haven't tried that on my M7 code yet. It had crossed my mind as something to try, but I avoided it because, of course in theory, we shouldn't be calling the GC our own, so I feel "guilty" doing it. :-D I...
by kwiley
Sun Jan 27, 2019 4:17 am
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

I realize you have admitted this is upcoming work, but I'm still curious if I'm "doing something wrong". I am getting consistent heap errors after my program runs for a minute or two. This isn't surprising since it repeatedly stomps all of the memory as it copies out an ROI from the sensor's latest ...
by kwiley
Sun Jan 27, 2019 2:25 am
Forum: Technical Discussion
Topic: M7 5V out?
Replies: 17
Views: 1587

Re: M7 5V out?

So I started by identifying the correct contact point. This photo indicates the 5V line of the USB (which would make for a much more challenging mod, as the attachment is minuscule and tucked into the board's circuitry) and the 5V anode of the diode (which is somewhat larger and considerably more is...
by kwiley
Sun Jan 27, 2019 1:53 am
Forum: General Topics
Topic: Pan & Tilt shield vs. Servo shield
Replies: 3
Views: 2023

Re: Pan & Tilt shield vs. Servo shield

Hmmm, so the servo shield can't read a given servo's position but the P&T can?
by kwiley
Sun Jan 27, 2019 1:04 am
Forum: General Topics
Topic: Pan & Tilt shield vs. Servo shield
Replies: 3
Views: 2023

Pan & Tilt shield vs. Servo shield

I saw the various posts about these shields, read their descriptions, and looked over their pinouts a bit. I think the similarities and differences are fairly clear at this point. If I understand correctly, the P&T shield drives up to three servos directly off the PWM GPIO pins and the Servo shield ...
by kwiley
Fri Jan 25, 2019 2:14 pm
Forum: Technical Discussion
Topic: M7 5V out?
Replies: 17
Views: 1587

Re: M7 5V out?

Ah, thanks! After you pointed me to the diode, I quickly found the correct contact with the multimeter. It's even one of the contacts toward the edge of the board instead of toward the middle (anode #2 according to the diode's datasheet). That will be a pretty easy connection to make. Sorry for all ...
by kwiley
Fri Jan 25, 2019 1:10 pm
Forum: Technical Discussion
Topic: M7 5V out?
Replies: 17
Views: 1587

Re: M7 5V out?

I was talking to my electronics buddy about the proposal of tapping into the USB 5V line and he asked why I couldn't just get 5V off of VIN while the USB power is plugged in. I told him it was my understanding that the VIN pin only operates as an alternate incoming power source to the M7, but not th...
by kwiley
Mon Jan 21, 2019 6:53 pm
Forum: Technical Discussion
Topic: Image.copy(): "OSError: Cannot copy to fb!"
Replies: 19
Views: 1264

Re: Image.copy(): "OSError: Cannot copy to fb!"

As an extra feature, it would be cool to run pooling and copy at the same time so as to perform ROI extraction and downsampling simultaneously. Currently, copy() doesn't have a pooling option and the pooling functions don't have an ROI option. Either approach could work in theory, although one might...

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