This way you will not able to scale the image. You need to figure out the principles.
Try to understand the advices in post #9 and #19.
Do you waiting for somebody, who write the code for you? May be better for you to move the topic to the "Paid work" category?
The Adafruit GFX documentation shows you how to write an nxm rectangle.
Thanks for the suggestions , I was able to scale the image by 2
But there is one issue , there is extra pixel data being printed .
The ad_img is actual scaled image and ad_img_2 is the extra data display
Below is the code
#include <SPI.h>
//#define USE_SDFAT
#include <SD.h>
#include <Adafruit_GFX.h> // Hardware-specific library
#include <MCUFRIEND_kbv.h>
MCUFRIEND_kbv tft;
#if defined(ESP32)
#define SD_CS 5
#else
#define SD_CS 10
#endif
#define NAMEMATCH "swiggy" // "" matches any name
//#define NAMEMATCH "" // *tiger*.bmp
#define PALETTEDEPTH 0 // do not support Palette modes
//#define PALETTEDEPTH 8 // support 256-colour Palette
char namebuf[32] = "/"; //BMP files in root directory
//char namebuf[32] = "/bitmaps/"; //BMP directory e.g. files in /bitmaps/*.bmp
File root;
int pathlen;
void setup()
{
uint16_t ID;
Serial.begin(9600);
Serial.print("Show BMP files on TFT with ID:0x");
ID = tft.readID();
Serial.println(ID, HEX);
if (ID == 0x0D3D3) ID = 0x9481;
tft.begin(ID);
tft.fillScreen(0x001F);
tft.setTextColor(0xFFFF, 0x0000);
tft.setRotation(1);
bool good = SD.begin(SD_CS);
if (!good) {
Serial.print(F("cannot start SD"));
while (1);
}
root = SD.open(namebuf);
pathlen = strlen(namebuf);
}
void loop()
{
char *nm = namebuf + pathlen;
File f = root.openNextFile();
uint8_t ret;
uint32_t start;
if (f != NULL) {
#ifdef USE_SDFAT
f.getName(nm, 32 - pathlen);
#else
strcpy(nm, (char *)f.name());
#endif
f.close();
strlwr(nm);
if (strstr(nm, ".bmp") != NULL && strstr(nm, NAMEMATCH) != NULL) {
Serial.print(namebuf);
Serial.print(F(" - "));
tft.fillScreen(0);
start = millis();
ret = showBMP(namebuf, 45, 55);
switch (ret) {
case 0:
Serial.print(millis() - start);
Serial.println(F("ms"));
delay(5000);
break;
case 1:
Serial.println(F("bad position"));
break;
case 2:
Serial.println(F("bad BMP ID"));
break;
case 3:
Serial.println(F("wrong number of planes"));
break;
case 4:
Serial.println(F("unsupported BMP format"));
break;
case 5:
Serial.println(F("unsupported palette"));
break;
default:
Serial.println(F("unknown"));
break;
}
}
}
else root.rewindDirectory();
}
#define BMPIMAGEOFFSET 54
#define BUFFPIXEL 20
uint16_t read16(File& f) {
uint16_t result; // read little-endian
f.read((uint8_t*)&result, sizeof(result));
return result;
}
uint32_t read32(File& f) {
uint32_t result;
f.read((uint8_t*)&result, sizeof(result));
return result;
}
uint8_t showBMP(char *nm, int x, int y)
{
Serial.println("start");
File bmpFile;
int bmpWidth, bmpHeight; // W+H in pixels
uint8_t bmpDepth; // Bit depth (currently must be 24, 16, 8, 4, 1)
uint32_t bmpImageoffset; // Start of image data in file
uint32_t rowSize; // Not always = bmpWidth; may have padding
uint8_t sdbuffer[3 * BUFFPIXEL]; // pixel in buffer (R+G+B per pixel)
uint16_t lcdbuffer[(1 << PALETTEDEPTH) + BUFFPIXEL], *palette = NULL;
uint8_t bitmask, bitshift;
boolean flip = true; // BMP is stored bottom-to-top
int w, h, row, col, lcdbufsiz = (1 << PALETTEDEPTH) + BUFFPIXEL, buffidx;
uint32_t pos; // seek position
boolean is565 = false; //
uint16_t bmpID;
uint16_t n; // blocks read
uint8_t ret;
if ((x >= tft.width()) || (y >= tft.height()))
return 1; // off screen
bmpFile = SD.open(nm); // Parse BMP header
bmpID = read16(bmpFile); // BMP signature
(void) read32(bmpFile); // Read & ignore file size
(void) read32(bmpFile); // Read & ignore creator bytes
bmpImageoffset = read32(bmpFile); // Start of image data
(void) read32(bmpFile); // Read & ignore DIB header size
bmpWidth = read32(bmpFile);
bmpHeight = read32(bmpFile);
n = read16(bmpFile); // # planes -- must be '1'
bmpDepth = read16(bmpFile); // bits per pixel
pos = read32(bmpFile); // format
if (bmpID != 0x4D42) ret = 2; // bad ID
else if (n != 1) ret = 3; // too many planes
else if (pos != 0 && pos != 3) ret = 4; // format: 0 = uncompressed, 3 = 565
else if (bmpDepth < 16 && bmpDepth > PALETTEDEPTH) ret = 5; // palette
else {
bool first = true;
is565 = (pos == 3); // ?already in 16-bit format
// BMP rows are padded (if needed) to 4-byte boundary
rowSize = (bmpWidth * bmpDepth / 8 + 3) & ~3;
if (bmpHeight < 0) { // If negative, image is in top-down order.
bmpHeight = -bmpHeight;
flip = false;
}
w = bmpWidth*2;
h = bmpHeight*2;
if ((x + w) >= tft.width()) // Crop area to be loaded
w = tft.width() - x;
if ((y + h) >= tft.height()) //
h = tft.height() - y;
if (bmpDepth <= PALETTEDEPTH) { // these modes have separate palette
//bmpFile.seek(BMPIMAGEOFFSET); //palette is always @ 54
bmpFile.seek(bmpImageoffset - (4<<bmpDepth)); //54 for regular, diff for colorsimportant
bitmask = 0xFF;
if (bmpDepth < 8)
bitmask >>= bmpDepth;
bitshift = 8 - bmpDepth;
n = 1 << bmpDepth;
lcdbufsiz -= n;
palette = lcdbuffer + lcdbufsiz;
for (col = 0; col < n; col++) {
pos = read32(bmpFile); //map palette to 5-6-5
palette[col] = ((pos & 0x0000F8) >> 3) | ((pos & 0x00FC00) >> 5) | ((pos & 0xF80000) >> 8);
}
}
// Set TFT address window to clipped image bounds
tft.setAddrWindow(x, y, x + w - 1, y + h - 1);
for (row = 0; row < h; row++) { // For each scanline...
uint8_t r, g, b, *sdptr;
int lcdidx, lcdleft;
if (flip) // Bitmap is stored bottom-to-top order (normal BMP)
pos = bmpImageoffset + (bmpHeight - 1 - row) * rowSize;
else // Bitmap is stored top-to-bottom
pos = bmpImageoffset + row * rowSize;
if (bmpFile.position() != pos) { // Need seek?
bmpFile.seek(pos);
buffidx = sizeof(sdbuffer); // Force buffer reload
}
for(int yscale=0;yscale<2; yscale++)
{
// Serial.println("row");
for (col = 0; col < w; ) { //pixels in row
lcdleft = w - col;
if (lcdleft > lcdbufsiz) lcdleft = lcdbufsiz;
for (lcdidx = 0; lcdidx < lcdleft; lcdidx++) { // buffer at a time
uint16_t color;
// Time to read more pixel data?
if (buffidx >= sizeof(sdbuffer)) { // Indeed
bmpFile.read(sdbuffer, sizeof(sdbuffer));
buffidx = 0; // Set index to beginning
r = 0;
}
switch (bmpDepth) { // Convert pixel from BMP to TFT format
case 32:
case 24:
b = sdbuffer[buffidx++];
g = sdbuffer[buffidx++];
r = sdbuffer[buffidx++];
if (bmpDepth == 32) buffidx++; //ignore ALPHA
color = tft.color565(r, g, b);
break;
case 16:
b = sdbuffer[buffidx++];
r = sdbuffer[buffidx++];
if (is565)
color = (r << 8) | (b);
else
color = (r << 9) | ((b & 0xE0) << 1) | (b & 0x1F);
break;
case 1:
case 4:
case 8:
if (r == 0)
b = sdbuffer[buffidx++], r = 8;
color = palette[(b >> bitshift) & bitmask];
r -= bmpDepth;
b <<= bmpDepth;
break;
}
for(int xscale=0;xscale<1;xscale++)
{
lcdbuffer[lcdidx] = color;
lcdidx++;
lcdbuffer[lcdidx] = color;
//Serial.println("pixel");
}
}
tft.pushColors(lcdbuffer, lcdidx, first);
first = false;
col += lcdidx;
} // end cols
}
}Serial.println("done");
tft.setAddrWindow(0, 0, tft.width() - 1, tft.height() - 1); //restore full screen
ret = 0;
Serial.println("inside set addr");// good render
}
bmpFile.close();
return (ret);
}
Please point these "extra pixels" in the picture, I don't understand what you mean.
Also, you first picture shown an empty screen, is it what you intended to show?
yes , those are the extra pixels -
the ad_img is shown first - which is scaled image by 2 but its followed by ad_img_2 .
Sorry, I did understood nothing from your answers.
Please use a google translate if English is not your native language.
sorry for my bad english.
if you look at the first image , its not empty screen but white box with lines . This entire box displayed in first image are extra data
The second image is the image that is scaled by 2.
The problem is that the image gets displayed followed by this white box with stripes.
I want to avoid this white box with stripes ( shown in image 1 )
Thanks for your explanation.
I am not sure that clearly see the problem, but perhaps you you need to fill an entire display with background color before showing the image?
You seem to have only partially understood my hint.
The idea is to keep the efficient coding using just one setAddrWindow() for drawing the BMP with the scaling factor of two.
For this you need to scale width and height for this method (setAddrWindow()) as well.
And you need a linebuffer of the scaled width, to be able to push it twice for each line, instead of the arbitrarily sized lcdbuffer. Hope your processor has enough RAM for this.
-jz-
A more intuitive solution would be to search for a BMP drawing example that draws it pixel by pixel using the drawPixel() method, and then replace drawPixel() with drawFilledRect() to draw 2x2 rectangles per pixel. But this solution would be considerably slower.