From 4523cf652f568f1fbb57bf9a10ae3caae785cd9f Mon Sep 17 00:00:00 2001 From: Eugene Kliuchnikov Date: Wed, 29 Oct 2025 15:18:00 +0100 Subject: [PATCH] Fix low memory rendering pipleline (#4495) Put together calculations of x0/xsize for ProcessRow Drive-by: fix formatting --- .../low_memory_render_pipeline.cc | 101 +++++++++++------- lib/jxl/render_pipeline/stage_blending.cc | 8 +- 2 files changed, 64 insertions(+), 45 deletions(-) diff -urp libjxl-0.10.3.orig/lib/jxl/render_pipeline/low_memory_render_pipeline.cc libjxl-0.10.3/lib/jxl/render_pipeline/low_memory_render_pipeline.cc --- libjxl-0.10.3.orig/lib/jxl/render_pipeline/low_memory_render_pipeline.cc 2024-06-27 07:10:08.000000000 -0500 +++ libjxl-0.10.3/lib/jxl/render_pipeline/low_memory_render_pipeline.cc 2026-02-24 03:19:07.065363322 -0600 @@ -581,16 +581,13 @@ Status LowMemoryRenderPipeline::RenderRe image_area_rect.CeilShiftRight(channel_shifts_[i][anyc_[i]]); } - ssize_t frame_x0 = - first_image_dim_stage_ == stages_.size() ? 0 : frame_origin_.x0; - ssize_t frame_y0 = - first_image_dim_stage_ == stages_.size() ? 0 : frame_origin_.y0; - size_t full_image_xsize = first_image_dim_stage_ == stages_.size() - ? frame_dimensions_.xsize_upsampled - : full_image_xsize_; - size_t full_image_ysize = first_image_dim_stage_ == stages_.size() - ? frame_dimensions_.ysize_upsampled - : full_image_ysize_; + JXL_DASSERT(0 <= first_trailing_stage_); + JXL_DASSERT(first_trailing_stage_ < first_image_dim_stage_); + JXL_DASSERT(first_image_dim_stage_ <= stages_.size()); + + bool offscreen = (first_image_dim_stage_ == stages_.size()); + ptrdiff_t frame_x0 = offscreen ? 0 : frame_origin_.x0; + ptrdiff_t frame_y0 = offscreen ? 0 : frame_origin_.y0; // Compute actual x-axis bounds for the current image area in the context of // the full image this frame is part of. As the left boundary may be negative, @@ -605,13 +602,30 @@ Status LowMemoryRenderPipeline::RenderRe full_image_x0 = 0; } ssize_t full_image_x1 = frame_x0 + image_area_rect.x1(); - full_image_x1 = std::min(full_image_x1, full_image_xsize); - // If the current image area is entirely outside of the visible image, there - // is no point in proceeding. Note: this uses the assumption that if there is - // a stage with observable effects (i.e. a kInput stage), it only appears - // after the stage that switches to image dimensions. - if (full_image_x1 <= full_image_x0) return true; + std::vector span(stages_.size()); + for (size_t i = 0; i < stages_.size(); ++i) { + if (i < first_trailing_stage_) { + span[i] = Rect(group_rect[i].x0(), 0, group_rect[i].xsize(), + image_rect_[i].ysize()); + } else if (i < first_image_dim_stage_) { + // Before the first_image_dim_stage_, coordinates are relative to the + // current frame. + size_t x0 = full_image_x0 - frame_x0; + size_t x1 = full_image_x1 - frame_x0; + size_t x_max = frame_dimensions_.xsize_upsampled; + size_t cropped_x1 = std::min(x1, x_max); + span[i] = Rect(x0, 0, std::max(0, cropped_x1 - x0), + frame_dimensions_.ysize_upsampled); + } else { + size_t x0 = full_image_x0; + size_t x1 = full_image_x1; + size_t x_max = full_image_xsize_; + size_t cropped_x1 = std::min(x1, x_max); + span[i] = Rect(x0, 0, std::max(0, cropped_x1 - x0), + full_image_ysize_); + } + } // Data structures to hold information about input/output rows and their // buffers. @@ -702,18 +716,17 @@ Status LowMemoryRenderPipeline::RenderRe ssize_t image_y = static_cast(group_rect[i].y0()) + y; // Do not produce rows in out-of-bounds areas. - if (image_y < 0 || - image_y >= static_cast(image_rect_[i].ysize())) { - continue; - } + if (image_y < 0) continue; + if (image_y >= static_cast(span[i].y1())) continue; // Get the input/output rows and potentially apply mirroring to the input. prepare_io_rows(y, i); // Produce output rows. + if (span[i].xsize() == 0) continue; JXL_RETURN_IF_ERROR(stages_[i]->ProcessRow( - input_rows[i], output_rows, xpadding_for_output_[i], - group_rect[i].xsize(), group_rect[i].x0(), image_y, thread_id)); + input_rows[i], output_rows, xpadding_for_output_[i], span[i].xsize(), + span[i].x0(), image_y, thread_id)); } // Process trailing stages, i.e. the final set of non-kInOut stages; they @@ -741,21 +754,24 @@ Status LowMemoryRenderPipeline::RenderRe // (and may be necessary for correctness, as some stages assume coordinates // are within bounds). ssize_t full_image_y = frame_y0 + image_area_rect.y0() + y; - if (full_image_y < 0 || - full_image_y >= static_cast(full_image_ysize)) { - continue; - } + if (full_image_y < 0) continue; - for (size_t i = first_trailing_stage_; i < stages_.size(); i++) { - // Before the first_image_dim_stage_, coordinates are relative to the - // current frame. - size_t x0 = - i < first_image_dim_stage_ ? full_image_x0 - frame_x0 : full_image_x0; - size_t y = - i < first_image_dim_stage_ ? full_image_y - frame_y0 : full_image_y; + for (size_t i = first_trailing_stage_; i < first_image_dim_stage_; i++) { + if (span[i].xsize() == 0) continue; + size_t y0 = image_area_rect.y0() + y; + if (y0 >= span[i].y1()) continue; JXL_RETURN_IF_ERROR(stages_[i]->ProcessRow( input_rows[first_trailing_stage_], output_rows, - /*xextra=*/0, full_image_x1 - full_image_x0, x0, y, thread_id)); + /*xextra=*/0, span[i].xsize(), span[i].x0(), y0, thread_id)); + } + + for (size_t i = first_image_dim_stage_; i < stages_.size(); i++) { + if (span[i].xsize() == 0) continue; + if (full_image_y >= static_cast(span[i].y1())) continue; + JXL_RETURN_IF_ERROR( + stages_[i]->ProcessRow(input_rows[first_trailing_stage_], output_rows, + /*xextra=*/0, span[i].xsize(), span[i].x0(), + full_image_y, thread_id)); } } return true;