Merge pull request #4 from adafruit/jpeg-mode

Jpeg mode

Author: tannewt

adafruit_ov2640.py

@@ -106,6 +106,7 @@
 
 OV2640_COLOR_RGB = 0
 OV2640_COLOR_YUV = 1
+OV2640_COLOR_JPEG = 2
 
 _IMAGE_MODE_Y8_DVP_EN = const(0x40)
 _IMAGE_MODE_JPEG_EN = const(0x10)
@@ -886,55 +887,70 @@
     ]
 )
 
-# _ov2640_settings_jpeg3 = bytes([
-#     _BANK_SEL, _BANK_DSP,
-#     _RESET, _RESET_JPEG | _RESET_DVP,
-#     _IMAGE_MODE, _IMAGE_MODE_JPEG_EN | _IMAGE_MODE_HREF_VSYNC,
-#     0xD7, 0x03,
-#     0xE1, 0x77,
-#     0xE5, 0x1F,
-#     0xD9, 0x10,
-#     0xDF, 0x80,
-#     0x33, 0x80,
-#     0x3C, 0x10,
-#     0xEB, 0x30,
-#     0xDD, 0x7F,
-#     _RESET, 0x00,
-# ])
-
-_ov2640_settings_yuv422 = bytes(
-    [
-        _BANK_SEL,
-        _BANK_DSP,
-        _RESET,
-        _RESET_DVP,
-        _IMAGE_MODE,
-        _IMAGE_MODE_YUV422,
-        0xD7,
-        0x01,
-        0xE1,
-        0x67,
-        _RESET,
-        0x00,
-    ]
-)
-
-_ov2640_settings_rgb565 = bytes(
-    [
-        _BANK_SEL,
-        _BANK_DSP,
-        _RESET,
-        _RESET_DVP,
-        _IMAGE_MODE,
-        _IMAGE_MODE_RGB565,
-        0xD7,
-        0x03,
-        0xE1,
-        0x77,
-        _RESET,
-        0x00,
-    ]
-)
+_ov2640_color_settings = {
+    OV2640_COLOR_JPEG: bytes(
+        [
+            _BANK_SEL,
+            _BANK_DSP,
+            _RESET,
+            _RESET_JPEG | _RESET_DVP,
+            _IMAGE_MODE,
+            _IMAGE_MODE_JPEG_EN | _IMAGE_MODE_HREF_VSYNC,
+            0xD7,
+            0x03,
+            0xE1,
+            0x77,
+            0xE5,
+            0x1F,
+            0xD9,
+            0x10,
+            0xDF,
+            0x80,
+            0x33,
+            0x80,
+            0x3C,
+            0x10,
+            0xEB,
+            0x30,
+            0xDD,
+            0x7F,
+            _RESET,
+            0x00,
+        ]
+    ),
+    OV2640_COLOR_YUV: bytes(
+        [
+            _BANK_SEL,
+            _BANK_DSP,
+            _RESET,
+            _RESET_DVP,
+            _IMAGE_MODE,
+            _IMAGE_MODE_YUV422,
+            0xD7,
+            0x01,
+            0xE1,
+            0x67,
+            _RESET,
+            0x00,
+        ]
+    ),
+    OV2640_COLOR_RGB: bytes(
+        [
+            _BANK_SEL,
+            _BANK_DSP,
+            _RESET,
+            _RESET_DVP,
+            _IMAGE_MODE,
+            _IMAGE_MODE_RGB565,
+            0xD7,
+            0x03,
+            0xE1,
+            0x77,
+            _RESET,
+            0x00,
+        ]
+    ),
+}
 
 
 class _RegBits:
@@ -1114,6 +1130,19 @@ def capture(self, buf):
                 captured image.  Note that this can be a ulab array or a displayio Bitmap.
         """
         self._imagecapture.capture(buf)
+        if self.colorspace == OV2640_COLOR_JPEG:
+            eoi = buf.find(b"\xff\xd9")
+            if eoi != -1:
+                # terminate the JPEG data just after the EOI marker
+                return memoryview(buf)[: eoi + 2]
+        return None
+
+    @property
+    def capture_buffer_size(self):
+        """Return the size of capture buffer to use with current resolution & colorspace settings"""
+        if self.colorspace == OV2640_COLOR_JPEG:
+            return self.width * self.height // 5
+        return self.width * self.height * 2
 
     @property
     def mclk_frequency(self):
@@ -1140,17 +1169,15 @@ def colorspace(self):
     @colorspace.setter
     def colorspace(self, colorspace):
         self._colorspace = colorspace
-        self._write_list(
-            _ov2640_settings_rgb565
-            if colorspace == OV2640_COLOR_RGB
-            else _ov2640_settings_yuv422
-        )
+        self._set_size_and_colorspace()
+
+    def _set_colorspace(self):
+        colorspace = self._colorspace
+        settings = _ov2640_color_settings[colorspace]
+
+        self._write_list(settings)
         # written twice?
-        self._write_list(
-            _ov2640_settings_rgb565
-            if colorspace == OV2640_COLOR_RGB
-            else _ov2640_settings_yuv422
-        )
+        self._write_list(settings)
         time.sleep(0.01)
 
     def deinit(self):
@@ -1168,8 +1195,8 @@ def size(self):
         """Get or set the captured image size, one of the ``OV2640_SIZE_`` constants."""
         return self._size
 
-    @size.setter
-    def size(self, size):
+    def _set_size_and_colorspace(self):
+        size = self._size
         width, height, ratio = _resolution_info[size]
         offset_x, offset_y, max_x, max_y = _ratio_table[ratio]
         mode = _OV2640_MODE_UXGA
@@ -1190,7 +1217,11 @@ def size(self, size):
             offset_y //= 2
 
         self._set_window(mode, offset_x, offset_y, max_x, max_y, width, height)
+
+    @size.setter
+    def size(self, size):
         self._size = size
+        self._set_size_and_colorspace()
 
     def _set_flip(self):
         bits = 0
@@ -1267,15 +1298,19 @@ def _set_window(
             ((height >> 6) & 0x04) | ((width >> 8) & 0x03),
         ]
 
-        pclk_auto = 1
+        pclk_auto = 0
         pclk_div = 8
         clk_2x = 0
-        clk_div = 7
+        clk_div = 0
+
+        if self._colorspace != OV2640_COLOR_JPEG:
+            pclk_auto = 1
+            clk_div = 7
 
         if mode == _OV2640_MODE_CIF:
             regs = _ov2640_settings_to_cif
-            # if pixformat is not jpeg:
-            clk_div = 3
+            if self._colorspace != OV2640_COLOR_JPEG:
+                clk_div = 3
         elif mode == _OV2640_MODE_SVGA:
             regs = _ov2640_settings_to_svga
         else:
@@ -1294,7 +1329,7 @@ def _set_window(
         time.sleep(0.01)
 
         # Reestablish colorspace
-        self.colorspace = self._colorspace
+        self._set_colorspace()
 
         # Reestablish test pattern
         if self._test_pattern:

docs/examples.rst

@@ -6,3 +6,39 @@ Ensure your device works with this simple test.
 .. literalinclude:: ../examples/ov2640_simpletest.py
     :caption: examples/ov2640_simpletest.py
     :linenos:
+
+Display an image from the camera on the Kaluga 1.3 board, if it is fitted with an ili9341 display.
+
+.. literalinclude:: ../examples/ov2640_displayio_kaluga1_3_ili9341.py
+    :caption: ../examples/ov2640_displayio_kaluga1_3_ili9341.py
+    :linenos:
+
+Display an image from the camera on the Kaluga 1.3 board, if it is fitted with an st7789 display.
+
+.. literalinclude:: ../examples/ov2640_displayio_kaluga1_3_st7789.py
+    :caption: ../examples/ov2640_displayio_kaluga1_3_st7789.py
+    :linenos:
+
+Display an image from the camera connected to a Raspberry Pi Pico with an st7789 2" display
+
+.. literalinclude:: ../examples/ov2640_displayio_pico_st7789_2in.py
+    :caption: ../examples/ov2640_displayio_pico_st7789_2in.py
+    :linenos:
+
+Save an image to internal flash on Kaluga 1.3
+
+.. literalinclude:: ../examples/ov2640_jpeg_kaluga1_3.py
+    :caption: ../examples/ov2640_jpeg_kaluga1_3.py
+    :linenos:
+
+``boot.py`` for the above program
+
+.. literalinclude:: ../examples/ov2640_jpeg_kaluga1_3_boot.py
+    :caption: ../examples/ov2640_jpeg_kaluga1_3_boot.py
+    :linenos:
+
+Preview images on LCD then save to SD on Kaluga 1.3 fitted with an ili9341 display
+
+.. literalinclude:: ../examples/ov2640_jpeg_sd_kaluga1_3.py
+    :caption: ../examples/ov2640_jpeg_sd_kaluga1_3.py
+    :linenos:

examples/ov2640_displayio_kaluga1_3_ili9341.py

@@ -12,9 +12,6 @@
 rotation=90!  This demo is for the ili9341.  If the display is garbled, try adding
 rotation=90, or try modifying it to use ST7799.
 
-The camera included with the Kaluga development kit is the incompatible OV2640,
-it won't work.
-
 The audio board must be mounted between the Kaluga and the LCD, it provides the
 I2C pull-ups(!)
 """

examples/ov2640_displayio_kaluga1_3_st7789.py

@@ -13,9 +13,6 @@
 of straight lines, it may be an ili9341.  If it has a bunch of wiggly traces,
 it may be an st7789.  If in doubt, try both demos.
 
-The camera included with the Kaluga development kit is the incompatible OV2640,
-it won't work.
-
 The audio board must be mounted between the Kaluga and the LCD, it provides the
 I2C pull-ups(!)
 """

examples/ov2640_jpeg_kaluga1_3.py

@@ -0,0 +1,55 @@
+# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
+# SPDX-FileCopyrightText: Copyright (c) 2021 Jeff Epler for Adafruit Industries
+#
+# SPDX-License-Identifier: Unlicense
+
+"""
+The Kaluga development kit comes in two versions (v1.2 and v1.3); this demo is
+tested on v1.3.
+
+The audio board must be mounted between the Kaluga and the LCD, it provides the
+I2C pull-ups(!)
+
+You also need to place ov2640_jpeg_kaluga1_3_boot.py at CIRCUITPY/boot.py
+and reset the board to make the internal flash readable by CircuitPython.
+You can make CIRCUITPY readable from your PC by booting CircuitPython in
+safe mode or holding the "MODE" button on the audio daughterboard while
+powering on or resetting the board.
+"""
+
+import board
+import busio
+import adafruit_ov2640
+
+
+bus = busio.I2C(scl=board.CAMERA_SIOC, sda=board.CAMERA_SIOD)
+cam = adafruit_ov2640.OV2640(
+    bus,
+    data_pins=board.CAMERA_DATA,
+    clock=board.CAMERA_PCLK,
+    vsync=board.CAMERA_VSYNC,
+    href=board.CAMERA_HREF,
+    mclk=board.CAMERA_XCLK,
+    mclk_frequency=20_000_000,
+    size=adafruit_ov2640.OV2640_SIZE_QVGA,
+)
+
+pid = cam.product_id
+ver = cam.product_version
+print(f"Detected pid={pid:x} ver={ver:x}")
+# cam.test_pattern = True
+
+cam.colorspace = adafruit_ov2640.OV2640_COLOR_JPEG
+b = bytearray(cam.capture_buffer_size)
+jpeg = cam.capture(b)
+
+print(f"Captured {len(jpeg)} bytes of jpeg data")
+try:
+    with open("/jpeg.jpg", "wb") as f:
+        f.write(jpeg)
+except OSError as e:
+    print(e)
+    print(
+        "A 'read-only filesystem' error occurs if you did not correctly install\nov2640_jpeg_kaluga1_3_boot.py as CIRCUITPY/boot.py and reset the board"
+    )
+print("Wrote to CIRCUITPY/jpeg.jpg")

examples/ov2640_jpeg_kaluga1_3_boot.py

@@ -0,0 +1,23 @@
+# SPDX-FileCopyrightText: 2017 Scott Shawcroft, written for Adafruit Industries
+# SPDX-FileCopyrightText: Copyright (c) 2021 Jeff Epler for Adafruit Industries
+#
+# SPDX-License-Identifier: Unlicense
+"""Use this file as CIRCUITPY/boot.py in conjunction with ov2640_jpeg_kaluga1_3.py
+
+It makes the CIRCUITPY filesystem writable to CircuitPython
+(and read-only to the PC) unless the "MODE" button on the audio
+daughterboard is held while the board is powered on or reset.
+"""
+
+import analogio
+import board
+import storage
+
+V_MODE = 1.98
+V_RECORD = 2.41
+
+a = analogio.AnalogIn(board.IO6)
+a_voltage = a.value * a.reference_voltage / 65535
+if abs(a_voltage - V_MODE) > 0.05:  # If mode is NOT pressed...
+    print("storage writable by CircuitPython")
+    storage.remount("/", readonly=False)