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How to check whether lip movement is significant using face landmarks in dlib?
by marc nicole Oct. 7, 2024

Oct. 7, 2024

I am trying to assess whether the lips of a person are moving too much while the mouth is closed (to conclude they are chewing). I try to assess the lip movement through landmarks (dlib) : Inspired by the mouth example ( https://github.com/mauckc/mouth-open/blob/master/detect_open_mouth.py#L17), and using it before the following function (as a primary condition for telling the person is chewing), I wrote the following function: def lips_aspect_ratio(shape): # grab the indexes of the facial landmarks for the lip (mStart, mEnd) = (61, 68) lip = shape[mStart:mEnd] print(len(lip)) # compute the euclidean distances between the two sets of # vertical lip landmarks (x, y)-coordinates # to reach landmark 68 I need to get lib[7] not lip[6] (while I get lip[7] I get IndexOutOfBoundError) A = dist.euclidean(lip[1], lip[6]) # 62, 68 B = dist.euclidean(lip[3], lip[5]) # 64, 66 # compute the euclidean distance between the horizontal # lip landmark (x, y)-coordinates C = dist.euclidean(lip[0], lip[4]) # 61, 65 # compute the lip aspect ratio mar = (A + B) / (2.0 * C) # return the lip aspect ratio return mar How to define an aspect ratio for the lips to conclude they are moving significantly? Is the mentioned function able to tell whether the lips are significantly moving while the mouth is closed?

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Re: [Tutor] Clarification on .format() Method and Negative Indices in Python
by avi.e.gross＠gmail.com Oct. 6, 2024

Oct. 6, 2024

Hi, I'm not responding to what was designed for this one of many ways to print but suggesting a way to get what you want another way. Consider using an fstring as in this example: >>> example="ABCDE" >>> example[-1] 'E' >>> print(f"last char in example is: {example[-1]}") last char in example is: E Anything in an f-string between curly braces is evaluated and replaced and negative numbers are supported. Of course, if someday they change your other way, feel free to use that. And, of course, you can preprocess what you want before using your print method into a small variable, as another workaround. -----Original Message----- From: Tutor <tutor-bounces+avi.e.gross=gmail.com(a)python.org> On Behalf Of Xingyuan Shi via Tutor Sent: Tuesday, September 24, 2024 10:23 PM To: tutor(a)python.org Subject: [Tutor] Clarification on .format() Method and Negative Indices in Python Dear Python Tutor Team, I hope you are having a great day. I have been learning more about Python’s string formatting, and I came across an interesting issue regarding the .format() method. Specifically, I was curious as to why negative indices like {-1} are not supported in this method, while negative indexing works perfectly with lists and other sequences in Python. For instance, I attempted to use the following code: print("{-1},{-1},{-1}".format(20, "example", 3.14)) I expected the placeholders {-1} to behave similarly to negative indices in lists, but it resulted in an error. I understand that .format() relies on positional arguments, but I wonder if there was a specific design rationale behind not allowing negative indices here. Could you shed some light on this design choice? Thank you very much for your time and for developing such an incredible language that I thoroughly enjoy learning. Best regards, Stone _______________________________________________ Tutor maillist - Tutor(a)python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor

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Type hint question
by Albert-Jan Roskam Sept. 26, 2024

Sept. 26, 2024

Hi, I just started using type hints and mypy so this is probably a basic question. Why doesn't like mypy the code below? Also, I noticed that mypy seems to favour LBYL (if isinstance) to EAFP (try-except), in the sense that doesn't understand the latter well. Is this true? I'm still learning to use mypy, but sometimes it feels a lot like "pleasing mypy". Then again, it has already helped me find some errors. from typing import TypeVar T = TypeVar("T") def try_int(value: T) -> T: try: return int(value.strip(" ")) except (TypeError, AttributeError, ValueError): return value n = try_int(" 1") I get this message: main.py:7: error: Incompatible return value type (got "int", expected "T") [return-value] main.py:7: error: "T" has no attribute "strip" [attr-defined] Found 2 errors in 1 file (checked 1 source file) Thanks! Albert-Jan

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How to stop a specific thread in Python 2.7?
by marc nicole Sept. 26, 2024

Sept. 26, 2024

Hello guys, I want to know how to kill a specific running thread (say by its id) for now I run and kill a thread like the following: # start thread thread1 = threading.Thread(target= self.some_func(), args=( ...,), ) thread1.start() # kill the thread event_thread1 = threading.Event() event_thread1.set() I know that set() will kill all running threads, but if there was thread2 as well and I want to kill only thread1? Thanks!

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Clarification on .format() Method and Negative Indices in Python
by Xingyuan Shi Sept. 26, 2024

Sept. 26, 2024

Dear Python Tutor Team, I hope you are having a great day. I have been learning more about Python’s string formatting, and I came across an interesting issue regarding the .format() method. Specifically, I was curious as to why negative indices like {-1} are not supported in this method, while negative indexing works perfectly with lists and other sequences in Python. For instance, I attempted to use the following code: print("{-1},{-1},{-1}".format(20, "example", 3.14)) I expected the placeholders {-1} to behave similarly to negative indices in lists, but it resulted in an error. I understand that .format() relies on positional arguments, but I wonder if there was a specific design rationale behind not allowing negative indices here. Could you shed some light on this design choice? Thank you very much for your time and for developing such an incredible language that I thoroughly enjoy learning. Best regards, Stone

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Side effect and return value
by Albert-Jan Roskam Sept. 21, 2024

Sept. 21, 2024

Hi, I've just read "Code that fits into your Brain". The author says a function with a side effect should not have a return value. But how would one write this function in order to do that? This looks totally fine to me: from uuid import UUID from requests import post def create_user(info: dict) -> UUID: resp = post("https://some-thing/user", json=info) resp.raise_for_status() return UUID(resp.json()["id"]) Thanks! AJ

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Getting a Process.start() error pickle.PicklingError: Can't pickle <type 'module'>: it's not found as __builtin__.module with Python 2.7
by marc nicole Sept. 4, 2024

Sept. 4, 2024

Hello, I am using Python 2.7 on Windows 10 and I want to launch a process independently of the rest of the code so that the execution continues while the started process proceeds. I am using Process().start() from Python 2.7 as follows: from multiprocessing import Process def do_something(text): print(text) if __name__ == "__main__": q = Process(target=do_something,args=("somecmd") ) q.start() # following code should execute right after the q.start() call (not until it returns) ..... But getting the error at the call of Process().start(): pickle.PicklingError: Can't pickle <type 'module'>: it's not found as __builtin__.module anybody could provide an alternative to call the function do_something() in a separate thread ?

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Dataclass question
by Albert-Jan Roskam Aug. 23, 2024

Aug. 23, 2024

Hi, I'm using dataclasses and one of the fields is has a bytes type. It could be the contents of a .zip or .csv. I don't want to see so much clutter in the logs or on the screen, so I'm looking for a neat way to omit most of the info from the dataclass object's representation. Using the code below, field "y" is not shown at all, which is not really what I want (but it's nice and clean). Field "z" is more like it, but it requires more code. Is there a better way? Maybe with pydantic? from dataclasses import field, dataclass class AbbreviatedBytes(bytes): def __repr__(self, width=2): r = super().__repr__() return r if len(self) < width else f"{r[:width + 1]} [...]'" @dataclass class Test: x : bytes = b"" y : bytes = field(default=b"", repr=False) z : bytes = b"" def __post_init__(self): self.z = AbbreviatedBytes(self.z) print(Test(b"aaaa", b"bbbb", b"cccc")) # output: Test(x=b'aaaa', z=b'c [...]') Best wishes, Albert-Jan

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Any Jupyter users?
by Alan Gauld Aug. 18, 2024

Aug. 18, 2024

I have a friend doing a CS degree and running into problems with a Python "program" in her data science course. I said I'd take a look although data analysis is not my forte. When I got there I was presented with a Jupyter/Anaconda environment and the program seemed to be effectively a long interactive session (which Jupyter can save and rerun) about 200+ lines. Most of which is simply calling into library functions from the anaconda stack plus a half dozen libraries installed by pip at the top of the session. The error (a valueError) when I got to it is raised deep inside one of the imported libraries and the traceback does not go all the way to the top (only 3 or 4 levels) so it's not clear where the student's code is calling the library (although I suspect it will be the line in Jupyter above the error trace... But that is not calling any of the functions listed in the traceback. I don't use Anaconda or Jupyter so I'm not sure what debugging facilities are available. Is there a way to generate a complete traceback? Are there ways to find out where a function is defined (which module?). I did a simple text search but it didn't find the highest function listed so I assume it's inside a module somewhere, but where? Are there any tracing facilities like the ability to step through/into a function? Also can you save a Jupyter session as a runnable python file (ie with all the output stuff removed or commented out)? That way we might get a more complete error trace from the vanilla interpreter. Or load it into a smart IDE like Visual Code that can jump up and down the stack. -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ http://www.amazon.com/author/alan_gauld Follow my photo-blog on Flickr at: http://www.flickr.com/photos/alangauldphotos

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Question
by Markis Gardner Aug. 14, 2024

Aug. 14, 2024

This is my first time - so I hope I am doing this correctly. A long time ago, back when VB 6 was still popular (boy I loved that language, but hated what they did to it in VB.NET. WIshed they still had it) and Yahoo messenger was still around. I wrote a SUPER SIMPLE ABBREVIATED form of messenger able to chat with other people. Is it possible to do it as a standalone program with Python? If yes, can you give me suggestions on what to read (please don't send me the code solution)? If no, what is the best that can be done with JUST python? Thank you! Markis -- I am a certified Education consultant with *both *PIER and ICEF. http://connect.pierapps.com/widgets/agencies/42472 Check out one of my inventions.. Laser Deflector! Laser Deflector (lasermirrorgame.com) <https://lasermirrorgame.com/>

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