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TIFF I/O - make read_stripped handle both RGBA and raw encoded strips (#3670)

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This commit is contained in:
artemp 2017-05-16 13:44:55 +02:00
parent 62260dd3d4
commit 1d95cad922
1 changed files with 20 additions and 17 deletions
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37
src/tiff_reader.cpp
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@ -399,12 +399,12 @@ image_any tiff_reader<T>::read_any_gray(std::size_t x0, std::size_t y0, std::siz
return image_any(std::move(data));
}
// TODO: temp disable and default to `scanline` method for stripped images.
//else if (read_method_ == stripped)
//{
// image_type data(width, height);
// read_stripped<image_type>(x0, y0, data);
// return image_any(std::move(data));
//}
else if (read_method_ == stripped)
{
image_type data(width, height);
read_stripped<image_type>(x0, y0, data);
return image_any(std::move(data));
}
else
{
TIFF* tif = open(stream_);
@ -501,10 +501,9 @@ struct tiff_reader_traits
return (TIFFReadEncodedTile(tif, TIFFComputeTile(tif, x, y, 0, 0), buf, tile_size) != -1);
}
static bool read_strip(TIFF * tif, std::size_t y, pixel_type * buf)
static bool read_strip(TIFF * tif, std::size_t y, std::size_t rows_per_strip, std::size_t strip_width, pixel_type * buf)
{
std::uint32_t strip_size = TIFFStripSize(tif);
return (TIFFReadEncodedStrip(tif, y, buf, strip_size) != -1);
return (TIFFReadEncodedStrip(tif, y/rows_per_strip, buf, -1) != -1);
}
};
@ -527,10 +526,15 @@ struct tiff_reader_traits<image_rgba8>
return false;
}
static bool read_strip(TIFF * tif, std::size_t y, pixel_type * buf)
static bool read_strip(TIFF * tif, std::size_t y, std::size_t rows_per_strip, std::size_t strip_width, pixel_type * buf)
{
if (TIFFReadRGBAStrip(tif, y, buf) != -1)
{
std::uint32_t strip_size = TIFFStripSize(tif);
for (std::size_t y = 0; y < rows_per_strip/2; ++y)
{
std::swap_ranges(buf + y * strip_width, buf + (y + 1) * strip_width, buf + (rows_per_strip - y - 1) * strip_width);
}
return true;
}
return false;
@ -698,7 +702,7 @@ void tiff_reader<T>::read_tiled(std::size_t x0,std::size_t y0, ImageData & image
}
if (pick_first_band)
{
std::uint32_t size = tile_width_ * tile_height_;
std::uint32_t size = tile_width_ * tile_height_ * sizeof(pixel_type);
for (std::uint32_t n = 0; n < size; ++n)
{
tile[n] = tile[n * bands_];
@ -737,29 +741,28 @@ void tiff_reader<T>::read_stripped(std::size_t x0, std::size_t y0, ImageData & i
tx1 = std::min(width + x0, width_);
std::size_t row = 0;
bool pick_first_band = (bands_ > 1) && (strip_size / (width_ * rows_per_strip_ * sizeof(pixel_type)) == bands_);
for (std::size_t y = start_y; y < end_y; y += rows_per_strip_)
{
ty0 = std::max(y0, y) - y;
ty1 = std::min(end_y, y + rows_per_strip_) - y;
if (!detail::tiff_reader_traits<ImageData>::read_strip(tif, y, strip.get()))
if (!detail::tiff_reader_traits<ImageData>::read_strip(tif, y, rows_per_strip_, width_, strip.get()))
{
MAPNIK_LOG_DEBUG(tiff_reader) << "TIFFRead(Encoded|RGBA)Strip failed at " << y << " for " << width_ << "/" << height_ << "\n";
break;
}
if (pick_first_band)
{
std::uint32_t size = width_ * rows_per_strip_;
std::uint32_t size = width_ * rows_per_strip_ * sizeof(pixel_type);
for (std::uint32_t n = 0; n < size; ++n)
{
strip[n] = strip[bands_ * n];
}
}
// This is in reverse because the TIFFRead(RGBA|Encoded)Strip reads inverted
for (std::size_t ty = ty1; ty > ty0; --ty)
//for (std::size_t ty = ty0; ty < ty1; ++ty)
for (std::size_t ty = ty0; ty < ty1; ++ty)
{
image.set_row(row++, tx0 - x0, tx1 - x0, &strip[(ty - 1) * width_ + tx0]);
image.set_row(row++, tx0 - x0, tx1 - x0, &strip[ty * width_ + tx0]);
}
}
}