Slideshow from jpegs in SD card directory

examples/dv_stick/CMakeLists.txt

@@ -1 +1,2 @@
 include(dv_stick_test.cmake)
+include(dv_slideshow.cmake)

examples/dv_stick/dv_slideshow.cmake

@@ -0,0 +1,21 @@
+set(OUTPUT_NAME dv_slideshow)
+
+add_executable(
+  ${OUTPUT_NAME}
+  dv_slideshow.cpp
+)
+
+target_compile_definitions(${OUTPUT_NAME} PRIVATE
+  SDCARD_SPI_BUS=spi1
+  SDCARD_PIN_SPI0_CS=15
+  SDCARD_PIN_SPI0_SCK=10
+  SDCARD_PIN_SPI0_MOSI=11
+  SDCARD_PIN_SPI0_MISO=12)
+
+# Pull in pico libraries that we need
+target_link_libraries(${OUTPUT_NAME} pico_stdlib dv_display hardware_i2c hardware_uart pico_graphics fatfs jpegdec sdcard)
+
+pico_enable_stdio_usb(${OUTPUT_NAME} 1)
+
+# create map/bin/hex file etc.
+pico_add_extra_outputs(${OUTPUT_NAME})

examples/dv_stick/dv_slideshow.cpp

@@ -0,0 +1,169 @@
+#include <cstdio>
+#include <math.h>
+
+#include <stdio.h>
+#include "hardware/gpio.h"
+#include "hardware/uart.h"
+#include "drivers/dv_display/dv_display.hpp"
+#include "libraries/pico_graphics/pico_graphics.hpp"
+
+#include "JPEGDEC.h"
+#include "drivers/fatfs/ff.h"
+
+using namespace pimoroni;
+
+#define FRAME_WIDTH 720
+#define FRAME_HEIGHT 480
+
+FATFS fs;
+FRESULT fr;
+
+DVDisplay display(FRAME_WIDTH, FRAME_HEIGHT);
+PicoGraphics_PenDV_RGB555 graphics(FRAME_WIDTH, FRAME_HEIGHT, display);
+
+JPEGDEC jpeg;
+struct {
+  int x, y;
+} jpeg_decode_options;
+
+void *jpegdec_open_callback(const char *filename, int32_t *size) {
+  FIL *fil = new FIL;
+  if(f_open(fil, filename, FA_READ)) {return nullptr;}
+  *size = f_size(fil);
+  return (void *)fil;
+}
+
+void jpegdec_close_callback(void *handle) {
+  f_close((FIL *)handle);
+  delete (FIL *)handle;
+}
+
+int32_t jpegdec_read_callback(JPEGFILE *jpeg, uint8_t *p, int32_t c) {
+  uint br; f_read((FIL *)jpeg->fHandle, p, c, &br);
+  return br;
+}
+
+int32_t jpegdec_seek_callback(JPEGFILE *jpeg, int32_t p) {
+  return f_lseek((FIL *)jpeg->fHandle, p) == FR_OK ? 1 : 0;
+}
+
+int jpegdec_draw_callback(JPEGDRAW *draw) {
+  uint16_t *p = draw->pPixels;
+
+  int xo = jpeg_decode_options.x;
+  int yo = jpeg_decode_options.y;
+
+  for(int y = 0; y < draw->iHeight; y++) {
+    for(int x = 0; x < draw->iWidth; x++) {
+      int sx = draw->x + x + xo;
+      int sy = draw->y + y + yo;
+
+      if(sx >= 0 && sx < graphics.bounds.w && x < draw->iWidthUsed &&
+         sy >= 0 && sy < graphics.bounds.h) {
+        const RGB565 col = *p;
+        graphics.set_pen((col & 0x1F) | ((col & 0xFFC0) >> 1));
+        graphics.pixel({sx, sy});
+      }
+
+      p++;
+    }
+  }
+
+  return 1; // continue drawing
+}
+
+void draw_jpeg(std::string filename) {
+  jpeg.open(
+    filename.c_str(),
+    jpegdec_open_callback,
+    jpegdec_close_callback,
+    jpegdec_read_callback,
+    jpegdec_seek_callback,
+    jpegdec_draw_callback
+  );
+
+  jpeg_decode_options.x = (FRAME_WIDTH - jpeg.getWidth()) >> 1;
+  jpeg_decode_options.y = (FRAME_HEIGHT - jpeg.getHeight()) >> 1;
+
+  jpeg.setPixelType(RGB565_LITTLE_ENDIAN);
+
+  printf("- starting jpeg decode..");
+  int start = millis();
+  jpeg.decode(0, 0, 0);
+  printf("done in %d ms!\n", int(millis() - start));
+
+  jpeg.close();
+}
+
+void on_uart_rx() {
+    while (uart_is_readable(uart1)) {
+        uint8_t ch = uart_getc(uart1);
+        putc(ch, stdout);
+    }
+}
+
+int main() {
+  set_sys_clock_khz(216000, true);
+
+  stdio_init_all();
+
+  // Relay UART RX from the display driver
+  gpio_set_function(5, GPIO_FUNC_UART);
+  uart_init(uart1, 115200);
+  uart_set_hw_flow(uart1, false, false);
+  uart_set_format(uart1, 8, 1, UART_PARITY_NONE);
+  uart_set_fifo_enabled(uart1, false);
+  irq_set_exclusive_handler(UART1_IRQ, on_uart_rx);
+  irq_set_enabled(UART1_IRQ, true);
+  uart_set_irq_enables(uart1, true, false);
+
+  constexpr uint BUTTON_A = 9;
+  gpio_init(BUTTON_A);
+  gpio_set_dir(BUTTON_A, GPIO_IN);
+  gpio_pull_up(BUTTON_A);
+
+  sleep_ms(5000);
+
+  display.init();
+  //display.test();
+
+  graphics.set_pen(0);
+  graphics.clear();
+  display.flip();
+  graphics.set_pen(0);
+  graphics.clear();
+
+  printf("mounting sd card.. ");
+  fr = f_mount(&fs, "", 1);
+  if (fr != FR_OK) {
+    printf("Failed to mount SD card, error: %d\n", fr);
+    return 0;
+  }
+  printf("done!\n");
+
+  printf("Listing sd card contents..\n");
+  FILINFO file;
+  auto dir = new DIR();
+  bool first = true;
+  constexpr int ms_per_image = 5000;
+  while (1) {
+    f_opendir(dir, "/images/");
+    while(f_readdir(dir, &file) == FR_OK && file.fname[0]) {
+        printf("- %s %lld\n", file.fname, file.fsize);
+
+        draw_jpeg(std::string("/images/") + file.fname);
+
+        if (!first) {
+          for (int w = 0; w < ms_per_image && gpio_get(BUTTON_A) == 1; w += 10) {
+            sleep_ms(10);
+          }
+        }
+        first = false;
+        display.flip();
+        graphics.set_pen(0);
+        graphics.clear();
+    }
+    f_closedir(dir);
+    printf("done!\n");
+  }
+}