update image capture et api pour simplifier

Author: lchevallier-teledyne

api.py

@@ -10,12 +10,9 @@
 import os
 
 
-fd = None
 ctrl_list=dict()
 
-def initialize(sensor_mode=2,v4l2_flux='/dev/video0'): # start the driver with a configurable sensor mode. (Initialization is necessary before using any other function)
-    global fd
-    fd = open(v4l2_flux, 'rb+', buffering=0) #open the device
+def initialize(fd,sensor_mode=2): # start the driver with a configurable sensor mode. (Initialization is necessary before using any other function)
 
     if(fd.closed): #check if it opened well
         print("error : can't open ",v4l2_flux)
@@ -52,48 +49,45 @@ def initialize(sensor_mode=2,v4l2_flux='/dev/video0'): # start the driver with a
         line=ctrls.readline()
 
     fmt = v4l2.v4l2_format()
-    fmt.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE;
-    fmt.fmt.pix.field = v4l2.V4L2_FIELD_NONE;
+    fmt.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
+    fmt.fmt.pix.field = v4l2.V4L2_FIELD_NONE
     if(sensor_mode==2):
         fmt.fmt.pix.width = 1920
         fmt.fmt.pix.height = 1080
-        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_GREY;
-        set_control_value("sensor_mode",2)
+        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_GREY
+        set_control_value(fd,"sensor_mode",2)
     elif(sensor_mode==0):
         fmt.fmt.pix.width = 1920
         fmt.fmt.pix.height = 1080
-        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_Y10;
-        set_control_value("sensor_mode",0)
+        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_Y10
+        set_control_value(fd,"sensor_mode",0)
     elif(sensor_mode==1):
         fmt.fmt.pix.width = 1920
         fmt.fmt.pix.height = 800
-        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_Y10;
-        set_control_value("sensor_mode",1)
+        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_Y10
+        set_control_value(fd,"sensor_mode",1)
     elif(sensor_mode==3):
-        fmt.fmt.pix.width = 1920;
+        fmt.fmt.pix.width = 1920
         fmt.fmt.pix.height = 80
-        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_GREY;
-        set_control_value("sensor_mode",3)
-    fcntl.ioctl(fd, v4l2.VIDIOC_S_FMT, fmt);
+        fmt.fmt.pix.pixelformat = v4l2.V4L2_PIX_FMT_GREY
+        set_control_value(fd,"sensor_mode",3)
+    fcntl.ioctl(fd, v4l2.VIDIOC_S_FMT, fmt)
 
-def close(v4l2_flux='/dev/video0'): # closes the access to the driver, must be used last, no other function must be called after this one (except if you want to do an initialization again)
+def close(fd): # closes the access to the driver, must be used last, no other function must be called after this one (except if you want to do an initialization again)
     if(fd == None):
         print("error : flux closed")
         exit(0)
     fd.close()
 
 
-def get_device(): # return the device 
-    return fd
-
-def get_device_controls(): # return all names of controls in an array
+def get_device_controls(fd): # return all names of controls in an array
     return ctrl_list.keys()
 
-def get_control_info(control_name): # return all information about control example (min, max, default value ...) in a dict.
+def get_control_info(fd,control_name): # return all information about control example (min, max, default value ...) in a dict.
     return ctrl_list[control_name]
 
 
-def set_controls(controls_dict): # use a dictionary to set controls to value
+def set_controls(fd,controls_dict): # use a dictionary to set controls to value
 
     if(fd ==None or fd.closed): #check if file opened
         print("error : initialize the connection with the function initialize()")
@@ -125,10 +119,10 @@ def set_controls(controls_dict): # use a dictionary to set controls to value
 
 
 
-def get_controls_info(): # return the dictionary with all controls informations 
+def get_controls_info(fd): # return the dictionary with all controls informations 
     return ctrl_list
 
-def set_control_value(control_name,value): # Allows to retrieve the whole value of a control from its name.
+def set_control_value(fd,control_name,value): # Allows to retrieve the whole value of a control from its name.
     if(fd ==None or fd.closed): #check if file opened
         print("error : initialize the connection with the function initialize()")
         exit(0)
@@ -155,7 +149,7 @@ def set_control_value(control_name,value): # Allows to retrieve the whole value
     ecs.controls = ec # set control list into the structure
     fcntl.ioctl(fd, v4l2.VIDIOC_S_EXT_CTRLS, ecs) #set the control using v4l2 drivers
 
-def get_control_value(control_name): # Allows to assign a value to a control from its name.
+def get_control_value(fd,control_name): # Allows to assign a value to a control from its name.
     if(fd == None or fd.closed):
         print("error : initialize the connection with the function initialize()")
         exit(0)

image_capture_example.py

@@ -10,77 +10,126 @@
 import mmap
 import time
 import api
-api.initialize(sensor_mode=1)
-fd = api.get_device()
-print(">> get device capabilities")
-cp = v4l2.v4l2_capability()
-fcntl.ioctl(fd, v4l2.VIDIOC_QUERYCAP, cp)
-
-
-print(">> device setup")
-
-print(">> init mmap capture")
-req = v4l2.v4l2_requestbuffers()
-req.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
-req.memory = v4l2.V4L2_MEMORY_MMAP
-req.count = 1  # nr of buffer frames
-fcntl.ioctl(fd, v4l2.VIDIOC_REQBUFS, req)  # tell the driver that we want some buffers 
-print("req.count", req.count)
-buffers = []
-
-
-print(">>> VIDIOC_QUERYBUF, mmap, VIDIOC_QBUF")
-for ind in range(req.count):
-    # setup a buffer
-    buf = v4l2.v4l2_buffer()
-    buf.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
-    buf.memory = v4l2.V4L2_MEMORY_MMAP
-    buf.index = ind
-    fcntl.ioctl(fd, v4l2.VIDIOC_QUERYBUF, buf)
-    mm = mmap.mmap(fd.fileno(), buf.length, mmap.MAP_SHARED, mmap.PROT_READ | mmap.PROT_WRITE, offset=buf.m.offset)
-    buffers.append(mm)
-    # queue the buffer for capture
-    fcntl.ioctl(fd, v4l2.VIDIOC_QBUF, buf)
-
-print(">> Start streaming")
-buf_type = v4l2.v4l2_buf_type(v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE)
-fcntl.ioctl(fd, v4l2.VIDIOC_STREAMON, buf_type)
-
-def take_image(image_name):
-    # IMPORTANT : Just bellow you can uncomment to clean the insternal queue of the driver
-#    for i in range(3):
-#        buf = v4l2.v4l2_buffer()
-#        buf.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
-#        buf.memory = v4l2.V4L2_MEMORY_MMAP
-#        fcntl.ioctl(fd, v4l2.VIDIOC_DQBUF, buf)  # get image from the driver queue
-#        mm = buffers[buf.index]
-#        mm.read(len(mm))
-#        mm.seek(0)
-#        fcntl.ioctl(fd, v4l2.VIDIOC_QBUF, buf)
-    # Reactivate streaming
-    with open(image_name, "wb") as binary_file:
+
+
+def take_image(fd,buffers,image_name): # FUNCTION TO TAKE AN IMAGE 
+    
+    # This clear the buffer of the driver carefull with this code you will use only 1/4 of the images. 
+    # Cleaning the buffer is only usefull for taking image not for  video streaming ...
+    # If you want to do a more video streaming applicaton just remove the for (the next 10 lines)
+    for i in range(3): 
         buf = v4l2.v4l2_buffer()
         buf.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
         buf.memory = v4l2.V4L2_MEMORY_MMAP
         fcntl.ioctl(fd, v4l2.VIDIOC_DQBUF, buf)  # get image from the driver queue
         mm = buffers[buf.index]
-        binary_file.write(mm.read(len(mm)))
+        mm.read(len(mm))
         mm.seek(0)
         fcntl.ioctl(fd, v4l2.VIDIOC_QBUF, buf)
 
-api.set_control_value("test_pattern",1)
-time.sleep(0.2)
-for i in range(1,10):
-    api.set_control_value("test_pattern",i%2+1)
+
+
+    with open(image_name, "wb") as binary_file: # Save the new image
+        buf = v4l2.v4l2_buffer()
+        buf.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
+        buf.memory = v4l2.V4L2_MEMORY_MMAP
+        fcntl.ioctl(fd, v4l2.VIDIOC_DQBUF, buf)  # get image from the driver queue
+        mm = buffers[buf.index]
+
+        image = mm.read(len(mm)) 
+
+        # Here you can add process to the image if you want 
+
+        binary_file.write(image) #This is writting your image in the file
+        mm.seek(0)
+        fcntl.ioctl(fd, v4l2.VIDIOC_QBUF, buf)
+
+
+
+
+def main():
+
+
+    fd = open("/dev/video0", 'rb+', buffering=0) #open the device
+
+
+    # sensor mode = 0 => height=1080 width=1920 format=Y10
+    # sensor mode = 1 => height=800 width=1920 format=Y10
+    # sensor mode = 2 => height=1080 width=1920 format=GRAY8
+    # sensor mode = 3 => height=800 width=1920 format=GRAY8
+
+    api.initialize(fd,sensor_mode=0) 
+
+
+
+
+    print(">> get device capabilities")
+    cp = v4l2.v4l2_capability()
+    fcntl.ioctl(fd, v4l2.VIDIOC_QUERYCAP, cp)
+
+
+    print(">> device setup")
+
+    print(">> init mmap capture")
+    req = v4l2.v4l2_requestbuffers()
+    req.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
+    req.memory = v4l2.V4L2_MEMORY_MMAP
+    req.count = 1  # nr of buffer frames
+    fcntl.ioctl(fd, v4l2.VIDIOC_REQBUFS, req)  # tell the driver that we want some buffers 
+    print("req.count", req.count)
+    buffers = []
+
+
+    print(">>> VIDIOC_QUERYBUF, mmap, VIDIOC_QBUF")
+    for ind in range(req.count): #create the buffers storage
+        # setup a buffer
+        buf = v4l2.v4l2_buffer()
+        buf.type = v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE
+        buf.memory = v4l2.V4L2_MEMORY_MMAP
+        buf.index = ind
+        fcntl.ioctl(fd, v4l2.VIDIOC_QUERYBUF, buf)
+        mm = mmap.mmap(fd.fileno(), buf.length, mmap.MAP_SHARED, mmap.PROT_READ | mmap.PROT_WRITE, offset=buf.m.offset)
+        buffers.append(mm)
+        # queue the buffer for capture
+        fcntl.ioctl(fd, v4l2.VIDIOC_QBUF, buf)
+
+
+    #start video streaming
+    print(">> Start streaming")
+    buf_type = v4l2.v4l2_buf_type(v4l2.V4L2_BUF_TYPE_VIDEO_CAPTURE)
+    fcntl.ioctl(fd, v4l2.VIDIOC_STREAMON, buf_type)
+
+
+    #all controls initialization
+    api.set_control_value(fd,"exposure",20000)
     time.sleep(0.2)
-    take_image("10bit_"+str(i)+".raw")
-    
 
-print(">> Stop streaming")
-fcntl.ioctl(fd, v4l2.VIDIOC_STREAMOFF, buf_type)
-for i in buffers:
-    i.close()
-api.close()
 
-  
-     
+    # the loop taking images
+
+    for i in range(0,10): #this will take 10 images
+
+
+
+        # You can add here any changes of the controls for the next image
+        # example  : 
+        #
+        # api.set_control_value(fd,"test_pattern",i%2+1)
+        #
+        # this example will do an image with the first test pattern, the second image will be with 
+        # the second test pattern, the third will be with the first test pattern again ...
+
+        time.sleep(0.2)
+
+        take_image(fd,buffers,"10bit_"+str(i)+".raw") # take image changing the name to save them properly
+        
+
+    print(">> Stop streaming")
+    fcntl.ioctl(fd, v4l2.VIDIOC_STREAMOFF, buf_type)
+    for i in buffers:
+        i.close()
+    api.close(fd)
+
+if __name__=="__main__":
+    main()
+