rdctype::array<byte> CaptureFile::GetThumbnail(FileType type, uint32_t maxsize)
{
rdctype::array<byte> buf;
Serialiser ser(Filename(), Serialiser::READING, false);
if(ser.HasError())
return buf;
ser.Rewind();
int chunkType = ser.PushContext(NULL, NULL, 1, false);
if(chunkType != THUMBNAIL_DATA)
return buf;
bool HasThumbnail = false;
ser.Serialise(NULL, HasThumbnail);
if(!HasThumbnail)
return buf;
byte *jpgbuf = NULL;
size_t thumblen = 0;
uint32_t thumbwidth = 0, thumbheight = 0;
{
ser.Serialise("ThumbWidth", thumbwidth);
ser.Serialise("ThumbHeight", thumbheight);
ser.SerialiseBuffer("ThumbnailPixels", jpgbuf, thumblen);
}
if(jpgbuf == NULL)
return buf;
// if the desired output is jpg and either there's no max size or it's already satisfied,
// return the data directly
if(type == FileType::JPG && (maxsize == 0 || (maxsize > thumbwidth && maxsize > thumbheight)))
{
create_array_init(buf, thumblen, jpgbuf);
}
else
{
// otherwise we need to decode, resample maybe, and re-encode
int w = (int)thumbwidth;
int h = (int)thumbheight;
int comp = 3;
byte *thumbpixels =
jpgd::decompress_jpeg_image_from_memory(jpgbuf, (int)thumblen, &w, &h, &comp, 3);
if(maxsize != 0)
{
uint32_t clampedWidth = RDCMIN(maxsize, thumbwidth);
uint32_t clampedHeight = RDCMIN(maxsize, thumbheight);
if(clampedWidth != thumbwidth || clampedHeight != thumbheight)
{
// preserve aspect ratio, take the smallest scale factor and multiply both
float scaleX = float(clampedWidth) / float(thumbwidth);
float scaleY = float(clampedHeight) / float(thumbheight);
if(scaleX < scaleY)
clampedHeight = uint32_t(scaleX * thumbheight);
else if(scaleY < scaleX)
clampedWidth = uint32_t(scaleY * thumbwidth);
byte *resizedpixels = (byte *)malloc(3 * clampedWidth * clampedHeight);
stbir_resize_uint8_srgb(thumbpixels, thumbwidth, thumbheight, 0, resizedpixels,
clampedWidth, clampedHeight, 0, 3, -1, 0);
free(thumbpixels);
thumbpixels = resizedpixels;
thumbwidth = clampedWidth;
thumbheight = clampedHeight;
}
}
std::vector<byte> encodedBytes;
switch(type)
{
case FileType::JPG:
{
int len = thumbwidth * thumbheight * 3;
encodedBytes.resize(len);
jpge::params p;
p.m_quality = 90;
jpge::compress_image_to_jpeg_file_in_memory(&encodedBytes[0], len, (int)thumbwidth,
(int)thumbheight, 3, thumbpixels, p);
encodedBytes.resize(len);
break;
}
case FileType::PNG:
{
stbi_write_png_to_func(&writeToByteVector, &encodedBytes, (int)thumbwidth, (int)thumbheight,
3, thumbpixels, 0);
break;
}
case FileType::TGA:
{
stbi_write_tga_to_func(&writeToByteVector, &encodedBytes, (int)thumbwidth, (int)thumbheight,
3, thumbpixels);
break;
}
case FileType::BMP:
{
stbi_write_bmp_to_func(&writeToByteVector, &encodedBytes, (int)thumbwidth, (int)thumbheight,
3, thumbpixels);
break;
}
default:
{
RDCERR("Unsupported file type %d in thumbnail fetch", type);
free(thumbpixels);
delete[] jpgbuf;
return buf;
}
}
buf = encodedBytes;
free(thumbpixels);
}
delete[] jpgbuf;
return buf;
}
JNIEXPORT jint JNICALL Java_org_lwjgl_stb_STBImageResize_nstbir_1resize_1uint8_1srgb(JNIEnv *__env, jclass clazz, jlong input_pixelsAddress, jint input_w, jint input_h, jint input_stride_in_bytes, jlong output_pixelsAddress, jint output_w, jint output_h, jint output_stride_in_bytes, jint num_channels, jint alpha_channel, jint flags) {
unsigned char const *input_pixels = (unsigned char const *)(intptr_t)input_pixelsAddress;
unsigned char *output_pixels = (unsigned char *)(intptr_t)output_pixelsAddress;
UNUSED_PARAMS(__env, clazz)
return (jint)stbir_resize_uint8_srgb(input_pixels, input_w, input_h, input_stride_in_bytes, output_pixels, output_w, output_h, output_stride_in_bytes, num_channels, alpha_channel, flags);
}
