Scale JPGs to size depending on cropped or fit.

This commit is contained in:
Jonas Diemer 2026-01-13 16:53:37 +01:00
parent b9cb412c1c
commit 32064f19ac
4 changed files with 11 additions and 6 deletions

View File

@ -372,7 +372,7 @@ bool Epub::generateCoverBmp(bool cropped) const {
if (coverImageHref.substr(coverImageHref.length() - 4) == ".jpg" ||
coverImageHref.substr(coverImageHref.length() - 5) == ".jpeg") {
Serial.printf("[%lu] [EBP] Generating BMP from JPG cover image\n", millis());
Serial.printf("[%lu] [EBP] Generating BMP from JPG cover image (%s mode)\n", millis(), cropped ? "cropped" : "fit");
const auto coverJpgTempPath = getCachePath() + "/.cover.jpg";
FsFile coverJpg;
@ -391,7 +391,7 @@ bool Epub::generateCoverBmp(bool cropped) const {
coverJpg.close();
return false;
}
const bool success = JpegToBmpConverter::jpegFileToBmpStream(coverJpg, coverBmp);
const bool success = JpegToBmpConverter::jpegFileToBmpStream(coverJpg, coverBmp, cropped);
coverJpg.close();
coverBmp.close();
SdMan.remove(coverJpgTempPath.c_str());

View File

@ -160,7 +160,7 @@ unsigned char JpegToBmpConverter::jpegReadCallback(unsigned char* pBuf, const un
}
// Core function: Convert JPEG file to 2-bit BMP
bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut, bool crop) {
Serial.printf("[%lu] [JPG] Converting JPEG to BMP\n", millis());
// Setup context for picojpeg callback
@ -201,8 +201,12 @@ bool JpegToBmpConverter::jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut) {
const float scaleToFitWidth = static_cast<float>(TARGET_MAX_WIDTH) / imageInfo.m_width;
const float scaleToFitHeight = static_cast<float>(TARGET_MAX_HEIGHT) / imageInfo.m_height;
// We scale to the smaller dimension, so we can potentially crop later.
// TODO: ideally, we already crop here.
const float scale = (scaleToFitWidth > scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
float scale = 1.0;
if (crop) { // if we will crop, scale to the smaller dimension
scale = (scaleToFitWidth > scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
} else { // else, scale to the larger dimension to fit
scale = (scaleToFitWidth < scaleToFitHeight) ? scaleToFitWidth : scaleToFitHeight;
}
outWidth = static_cast<int>(imageInfo.m_width * scale);
outHeight = static_cast<int>(imageInfo.m_height * scale);

View File

@ -11,5 +11,5 @@ class JpegToBmpConverter {
unsigned char* pBytes_actually_read, void* pCallback_data);
public:
static bool jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut);
static bool jpegFileToBmpStream(FsFile& jpegFile, Print& bmpOut, bool crop = true);
};

View File

@ -239,6 +239,7 @@ void SleepActivity::renderCoverSleepScreen() const {
if (SdMan.openFileForRead("SLP", coverBmpPath, file)) {
Bitmap bitmap(file);
if (bitmap.parseHeaders() == BmpReaderError::Ok) {
Serial.printf("[SLP] Rendering sleep cover: %s\n", coverBmpPath);
renderBitmapSleepScreen(bitmap);
return;
}