Extract crop_source_pointers().

diff --git a/src/lib/image.cc b/src/lib/image.cc
index 7181c4546e42b86450c94b6e8e97e9e3acb77b60..f1586be4ddd46f3ffc4988c499b4f5cc5c60e74f 100644 (file)
--- a/src/lib/image.cc
+++ b/src/lib/image.cc
@@ -160,6 +160,45 @@ round_height_for_subsampling (int p, AVPixFmtDescriptor const * desc)
 }
 
 
+pair<vector<uint8_t*>, dcp::Size>
+Image::crop_source_pointers(Crop crop) const
+{
+       auto descriptor = av_pix_fmt_desc_get(_pixel_format);
+       if (!descriptor) {
+               throw PixelFormatError("crop_source_pointers()", _pixel_format);
+       }
+
+       /* Round down so that we crop only the number of pixels that is straightforward
+        * considering any subsampling.
+        */
+       Crop corrected_crop(
+               round_width_for_subsampling(crop.left, descriptor),
+               round_width_for_subsampling(crop.right, descriptor),
+               round_height_for_subsampling(crop.top, descriptor),
+               round_height_for_subsampling(crop.bottom, descriptor)
+               );
+
+       /* Also check that we aren't cropping more image than there actually is */
+       if ((corrected_crop.left + corrected_crop.right) >= (size().width - 4)) {
+               corrected_crop.left = 0;
+               corrected_crop.right = size().width - 4;
+       }
+
+       if ((corrected_crop.top + corrected_crop.bottom) >= (size().height - 4)) {
+               corrected_crop.top = 0;
+               corrected_crop.bottom = size().height - 4;
+       }
+
+       std::vector<uint8_t*> pointers(planes());
+       for (int c = 0; c < planes(); ++c) {
+               int const x = lrintf(bytes_per_pixel(c) * corrected_crop.left);
+               pointers[c] = data()[c] + x + stride()[c] * (corrected_crop.top / vertical_factor(c));
+       }
+
+       return { pointers, corrected_crop.apply(size()) };
+}
+
+
 /** Crop this image, scale it to `inter_size' and then place it in a black frame of `out_size'.
  *  @param crop Amount to crop by.
  *  @param inter_size Size to scale the cropped image to.
@@ -196,34 +235,9 @@ Image::crop_scale_window (
        auto out = make_shared<Image>(out_format, out_size, out_alignment);
        out->make_black ();
 
-       auto in_desc = av_pix_fmt_desc_get (_pixel_format);
-       if (!in_desc) {
-               throw PixelFormatError ("crop_scale_window()", _pixel_format);
-       }
-
-       /* Round down so that we crop only the number of pixels that is straightforward
-        * considering any subsampling.
-        */
-       Crop corrected_crop(
-               round_width_for_subsampling(crop.left, in_desc),
-               round_width_for_subsampling(crop.right, in_desc),
-               round_height_for_subsampling(crop.top, in_desc),
-               round_height_for_subsampling(crop.bottom, in_desc)
-               );
-
-       /* Also check that we aren't cropping more image than there actually is */
-       if ((corrected_crop.left + corrected_crop.right) >= (size().width - 4)) {
-               corrected_crop.left = 0;
-               corrected_crop.right = size().width - 4;
-       }
-
-       if ((corrected_crop.top + corrected_crop.bottom) >= (size().height - 4)) {
-               corrected_crop.top = 0;
-               corrected_crop.bottom = size().height - 4;
-       }
-
-       /* Size of the image after any crop */
-       auto const cropped_size = corrected_crop.apply (size());
+       vector<uint8_t*> scale_in_data;
+       dcp::Size cropped_size;
+       std::tie(scale_in_data, cropped_size) = crop_source_pointers(crop);
 
        /* Scale context for a scale from cropped_size to inter_size */
        auto scale_context = sws_getContext (
@@ -260,13 +274,6 @@ Image::crop_scale_window (
                0, 1 << 16, 1 << 16
                );
 
-       /* Prepare input data pointers with crop */
-       uint8_t* scale_in_data[planes()];
-       for (int c = 0; c < planes(); ++c) {
-               int const x = lrintf(bytes_per_pixel(c) * corrected_crop.left);
-               scale_in_data[c] = data()[c] + x + stride()[c] * (corrected_crop.top / vertical_factor(c));
-       }
-
        auto out_desc = av_pix_fmt_desc_get (out_format);
        if (!out_desc) {
                throw PixelFormatError ("crop_scale_window()", out_format);
@@ -286,7 +293,7 @@ Image::crop_scale_window (
 
        sws_scale (
                scale_context,
-               scale_in_data, stride(),
+               scale_in_data.data(), stride(),
                0, cropped_size.height,
                scale_out_data, out->stride()
                );

diff --git a/src/lib/image.h b/src/lib/image.h
index dd9f8b840f86b578bcdbfd4c42473e0c16d70fb5..ce4382a42e5ca8c3b9c5d8bac48a709697ac1d09 100644 (file)
--- a/src/lib/image.h
+++ b/src/lib/image.h
@@ -111,6 +111,7 @@ private:
        void yuv_16_black (uint16_t, bool);
        static uint16_t swap_16 (uint16_t);
        void video_range_to_full_range ();
+       std::pair<std::vector<uint8_t*>, dcp::Size> crop_source_pointers(Crop crop) const;
 
        dcp::Size _size;
        AVPixelFormat _pixel_format; ///< FFmpeg's way of describing the pixel format of this Image