Faster bmp loading

Inkplate.cpp

@@ -1012,9 +1012,11 @@ int Inkplate::drawMonochromeBitmapSd(SdFile *f, struct bitmapHeader bmpHeader, i
     int i, j;
     for (j = 0; j < h; j++)
     {
+        uint8_t *bufferPtr = pixelBuffer;
+        f->read(pixelBuffer, w * 4);
         for (i = 0; i < w; i++)
         {
-            uint32_t pixelRow = f->read() << 24 | f->read() << 16 | f->read() << 8 | f->read();
+            uint32_t pixelRow = *(bufferPtr++) << 24 | *(bufferPtr++) << 16 | *(bufferPtr++) << 8 | *(bufferPtr++);
             if (invert)
                 pixelRow = ~pixelRow;
             for (int n = 0; n < 32; n++)
@@ -1048,9 +1050,11 @@ int Inkplate::drawGrayscaleBitmap4Sd(SdFile *f, struct bitmapHeader bmpHeader, i
     int i, j;
     for (j = 0; j < h; j++)
     {
+        uint8_t *bufferPtr = pixelBuffer;
+        f->read(pixelBuffer, w * 4);
         for (i = 0; i < w; i++)
         {
-            uint32_t pixelRow = f->read() << 24 | f->read() << 16 | f->read() << 8 | f->read();
+            uint32_t pixelRow = *(bufferPtr++) << 24 | *(bufferPtr++) << 16 | *(bufferPtr++) << 8 | *(bufferPtr++);
             if (invert)
                 pixelRow = ~pixelRow;
             for (int n = 0; n < 8; n++)
@@ -1082,13 +1086,15 @@ int Inkplate::drawGrayscaleBitmap8Sd(SdFile *f, struct bitmapHeader bmpHeader, i
     int i, j;
     for (j = 0; j < h; j++)
     {
+        uint8_t *bufferPtr = pixelBuffer;
+        f->read(pixelBuffer, w);
         for (i = 0; i < w; i++)
         {
             uint8_t px = 0;
             if (invert)
-                px = 255 - f->read();
+                px = 255 - *(bufferPtr++);
             else
-                px = f->read();
+                px = *(bufferPtr++);
             drawPixel(i + x, h - 1 - j + y, px >> 5);
         }
         if (padding)
@@ -1112,6 +1118,8 @@ int Inkplate::drawGrayscaleBitmap24Sd(SdFile *f, struct bitmapHeader bmpHeader,
     int i, j;
     for (j = 0; j < h; j++)
     {
+        uint8_t *bufferPtr = pixelBuffer;
+        f->read(pixelBuffer, w * 3);
         for (i = 0; i < w; i++)
         {
             //This is the proper way of converting True Color (24 Bit RGB) bitmap file into grayscale, but it takes waaay too much time (full size picture takes about 17s to decode!)
@@ -1119,12 +1127,12 @@ int Inkplate::drawGrayscaleBitmap24Sd(SdFile *f, struct bitmapHeader bmpHeader,
             //px = pow(px, 1.5);
             //display.drawPixel(i + x, h - j + y, (uint8_t)(px*7));
 
-            //So then, we are convertng it to grayscale using good old average and gamma correction (from LUT). With this metod, it is still slow (full size image takes 4 seconds), but much beter than prev mentioned method.
             uint8_t px = 0;
+            //So then, we are convertng it to grayscale using good old average and gamma correction (from LUT). With this metod, it is still slow (full size image takes 4 seconds), but much beter than prev mentioned method.
             if (invert)
-                px = ((255 - f->read()) * 2126 / 10000) + ((255 - f->read()) * 7152 / 10000) + ((255 - f->read()) * 722 / 10000);
+                px = ((255 - *(bufferPtr++)) * 2126 / 10000) + ((255 - *(bufferPtr++)) * 7152 / 10000) + ((255 - *(bufferPtr++)) * 722 / 10000);
             else
-                px = (f->read() * 2126 / 10000) + (f->read() * 7152 / 10000) + (f->read() * 722 / 10000);
+                px = (*(bufferPtr++) * 2126 / 10000) + (*(bufferPtr++) * 7152 / 10000) + (*(bufferPtr++) * 722 / 10000);
             //drawPixel(i + x, h - j + y, gammaLUT[px]);
             drawPixel(i + x, h - 1 - j + y, px >> 5);
             //drawPixel(i + x, h - j + y, px/32);

Inkplate.h

@@ -223,6 +223,7 @@ public:
 
 private:
     uint8_t gammaLUT[256];
+    uint8_t pixelBuffer[800 * 3 + 5];
     int8_t _temperature;
     uint8_t _panelOn = 0;
     uint8_t _rotation = 0;

bmpTestScript/bmpTestScript.ino

@@ -0,0 +1,83 @@
+#include "Inkplate.h"
+#include "SdFat.h"  
+
+Inkplate display(INKPLATE_3BIT);
+SdFile file;
+
+void setup() {
+    Serial.begin(115200);
+
+    display.begin();
+    display.clearDisplay();
+    display.display();
+}
+
+void loop() {
+    if (display.sdCardInit()) {
+        Serial.println("1");
+        display.println("SD Card OK! Reading image...");
+        display.partialUpdate();
+
+        if (!display.drawBitmapFromSD("1bit.bmp", 0, 0, 1)) {
+            display.println("Image open error");
+            display.display();
+        }
+        display.display();
+    }
+
+    delay(5000);
+    display.clearDisplay();
+    display.clean();
+    display.display();
+
+    if (display.sdCardInit()) {
+        Serial.println("2");
+        display.println("SD Card OK! Reading image...");
+        display.partialUpdate();
+
+        if (!display.drawBitmapFromSD("4bit.bmp", 0, 0)) {
+            display.println("Image open error");
+            display.display();
+        }
+        display.display();
+    }
+
+    delay(5000);
+    display.clearDisplay();
+    display.clean();
+    display.display();
+
+    if (display.sdCardInit()) {
+        Serial.println("3");
+        display.println("SD Card OK! Reading image...");
+        display.partialUpdate();
+
+        if (!display.drawBitmapFromSD("8bit.bmp", 0, 0)) {
+            display.println("Image open error");
+            display.display();
+        }
+        display.display();
+    }
+
+    delay(5000);
+    display.clearDisplay();
+    display.clean();
+    display.display();
+
+    if (display.sdCardInit()) {
+        Serial.println("4");
+        display.println("SD Card OK! Reading image...");
+        display.partialUpdate();
+
+        if (!display.drawBitmapFromSD("24bit.bmp", 0, 0)) {
+            display.println("Image open error");
+            display.display();
+        }
+        display.display();
+    }
+
+    delay(5000);
+    display.clearDisplay();
+    display.clean();
+    display.display();
+}

examples/2. Advanced Inkplate Features/5-Inkplate_SD_BMP_pictures/5-Inkplate_SD_BMP_pictures.ino

@@ -27,6 +27,8 @@ Inkplate display(INKPLATE_1BIT);    //Create an object on Inkplate library and a
 SdFile file;                        //Create SdFile object used for accessing files on SD card
 
 void setup() {
+    Serial.begin(115200);
+
     display.begin();                  //Init Inkplate library (you should call this function ONLY ONCE)
     display.clearDisplay();           //Clear frame buffer of display
     display.display();                //Put clear image on display
@@ -40,23 +42,24 @@ void setup() {
         //NOTE: Both drawBitmapFromSD methods allow for an optional fourth "invert" parameter. Setting this parameter to true
         //will flip all colors on the image, making black white and white black. This may be necessary when exporting bitmaps from
         //certain softwares.
-    if(!display.drawBitmapFromSD("image1.bmp", 0, 0)) {
+        if (!display.drawBitmapFromSD("image1.bmp", 0, 0)) {
             //If is something failed (wrong filename or wrong bitmap format), write error message on the screen.
             //REMEMBER! You can only use Windows Bitmap file with color depth of 1, 4, 8 or 24 bits with no compression! 
             display.println("Image open error");
             display.display();
         }
         display.display();
-  } else {
+    }
+    else {
         //If SD card init not success, display error on screen and stop the program (using infinite loop)
         display.println("SD Card error!");
         display.partialUpdate();
-    while(true);
+        while (true);
     }
     delay(5000);
 
     //Now try to load image using SdFat library class (for more advanced users) and display image on epaper.
-  if(file.open("image2.bmp", O_RDONLY)) {
+    if (file.open("image2.bmp", O_RDONLY)) {
         display.drawBitmapFromSD(&file, 0, 0);
         display.display();
     }