Horizontal bar in all images after certain images persists

[mockthebear]

Aparently I cannot repoen the issue #42
So i'm creating another one addressing the same issue at #42

I just tried the changes at master.
Still got the line there.
And bringing new insight:

  delete []png;
  png = (PNG*)ps_malloc(sizeof(PNG));

Doing this every time I decode a PNG dont fix it. Aparently is a poisoning in some static allocated variable?
At first i tought might be something beeing written in any of those order[19], lbase, lext, dbase or dext. But even changing them to const and removing the static the behavior persists.

Honestly, I don't know whats going on :(

And yes, the change is present:

#if ((INTPTR_MAX == INT64_MAX) || defined(HAL_ESP32_HAL_H_) || defined(TEENSYDUINO) || defined(ARM_MATH_CM4) || defined(ARM_MATH_CM7)) && !defined(ARDUINO_ARCH_RP2040)
//#define ALLOWS_UNALIGNED
#endif

Describe the bug

Having two images. Image A and image B.
Decode image A, it will be perfect. Decode image B, then B will have a red vertical bar all over its extension.
Invert the order, B then A, is all fine. Its seems to be some issue in image A that leaks trough the decompressor.

To Reproduce

Steps to reproduce the behavior:

Get an esp32s3 with an SD card (Might be still happening between other esps).
Use a code like this. Happens with any code, just providing the one i used)

#include <Arduino.h>
#include <SD.h>
#include <PNGdec.h>
#include "SPI.h"
#include <string>


#define SPI_CS 38
#define SPI_MOSI 14
#define SPI_MISO 47
#define SPI_SCK 21
#define SPI_MAX_CLOCK (40 * 1000 * 1000)

#define PANEL_WIDTH 64
#define PANEL_HEIGHT 32
#define FILE_PIXEL_COUNT PANEL_WIDTH * PANEL_HEIGHT
#define FILE_SIZE_BULK_SIZE ( FILE_PIXEL_COUNT * sizeof(uint16_t) )

File getFile(const char *name){
  File myFile = SD.open(name);
  return myFile;
}  

uint16_t* tmpBuffer;
File pngDecFile;
PNG *png=nullptr;

void * myOpen(const char *filename, int32_t *size) {
  pngDecFile = SD.open(filename);
  *size = pngDecFile.size();
  return &pngDecFile;
}
void myClose(void *handle) {
  if (pngDecFile) pngDecFile.close();
}
int32_t myRead(PNGFILE *handle, uint8_t *buffer, int32_t length) {
  if (!pngDecFile) return 0;
  return pngDecFile.read(buffer, length);
}
int32_t mySeek(PNGFILE *handle, int32_t position) {
  if (!pngDecFile) return 0;
  return pngDecFile.seek(position);
}

// Function to draw pixels to the display
int PNGDraw(PNGDRAW *pDraw) {
  static uint16_t raw[128];
  png->getLineAsRGB565(pDraw, raw, PNG_RGB565_LITTLE_ENDIAN, 0xffffffff);
  memcpy(tmpBuffer + (pDraw->y *pDraw->iWidth), raw, pDraw->iWidth * sizeof(uint16_t));
  return 1;
}


uint16_t *DecodePNGForBuffer(const char *name, int& rcError){
  auto fp = getFile(name);
  if (!fp){
    rcError = 998;
    return nullptr;
  }
  fp.close();


  png = new PNG;

  rcError = png->open(name, myOpen, myClose, myRead, mySeek, PNGDraw);
  if (rcError != PNG_SUCCESS) {
    delete png;
    return nullptr;
  }
   Serial.printf("File is size %d %d\n", png->getWidth(), png->getHeight());
  if (png->getWidth() != PANEL_WIDTH && png->getHeight() != PANEL_HEIGHT){
    Serial.printf("Mismatched image size, expected %d %d but got %d %d", PANEL_WIDTH, PANEL_HEIGHT, png->getWidth(), png->getHeight());
    png->close();
    rcError = 999;
    delete png;
    return nullptr;
  }
 
  tmpBuffer = (uint16_t*)ps_malloc(FILE_SIZE_BULK_SIZE );
  png->decode(NULL, 0);
  png->close();
  int x = 0;
  int y = 0;
  Serial.printf("[00]=");
  for (int i=0;i<FILE_SIZE_BULK_SIZE;i++){
    uint16_t color = tmpBuffer[i];
    Serial.printf("%05d,", color);
    x++;
    if (x > PANEL_WIDTH){
      x = 0;
      y++;
      Serial.printf("\n[%02d]=", y);
    }
  }
  Serial.printf("\n\n\nFinished file: %s!\n", name);
  delete png;
  return tmpBuffer;
}

void setup() {
  
  Serial.begin(115200);
  SPI.begin(SPI_SCK, SPI_MISO, SPI_MOSI, SPI_CS);
  SPI.setFrequency(SPI_MAX_CLOCK);
  Serial.println("Initializing SD card...");
  if(!SD.begin(SPI_CS, SPI, SPI_MAX_CLOCK, "/sd", 10)){
      return;
  }   
  Serial.println("SD OK!");


  int error;
  uint16_t *buffA = DecodePNGForBuffer("/imagea.png", error);
  uint16_t *buffB = DecodePNGForBuffer("/imageb.png", error);


}


void loop() {}

Flash it, and load those two images in to the SD card:
Image Image

https://dogurai.com/imagea.png
https://dogurai.com/imageb.png
Or here as zip:

images.zip

Checking the console will output the image pixels, those are 64x32 pixel images.
You will see this o the first lines of the imageb

Finished file: /expressions/imagec.png!
File is size 64 32
[00]=00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,00000,63488,00000,

That 63488 was'nt supposed to be there, it happens on the same row of every single line. Sometimes taking 4 rows, sometimes taking one.

Image

Expected behavior

No red line visible

Image you're having trouble with
https://dogurai.com/imagea.png
https://dogurai.com/imageb.png

Additional context

I hosted the images in a site i own so you can download without any tool compressing it in any way. I know its a encoding related issue, because loading the image using mspaint, editing any pixel and saving again solve the issue.

The original image as edited using paintnet, but i saw this happening with some images done by phone.