Method resize

subprojects/llama.cpp/tools/mtmd/clip.cpp:2243–2300

    };

    static void resize(
            const clip_image_u8 & src,
            clip_image_u8 & dst,
            const clip_image_size & target_resolution,
            resize_algo algo,
            bool add_padding = true, // TODO: define the behavior for add_padding = false
            std::array<uint8_t, 3> pad_color = {0, 0, 0}) {
        dst.nx = target_resolution.width;
        dst.ny = target_resolution.height;
        dst.buf.resize(3 * dst.nx * dst.ny);

        if (dst.nx == src.nx && dst.ny == src.ny) {
            // no resize needed, simple copy
            dst.buf = src.buf;
            return;
        }

        if (!add_padding) {
            // direct resize
            switch (algo) {
                case RESIZE_ALGO_BILINEAR:
                    resize_bilinear(src, dst, target_resolution.width, target_resolution.height);
                    break;
                case RESIZE_ALGO_BICUBIC:
                    resize_bicubic(src, dst, target_resolution.width, target_resolution.height);
                    break;
                default:
                    throw std::runtime_error("Unsupported resize algorithm");
            }
        } else {
            // resize with padding
            clip_image_u8 resized_image;
            float scale_w = static_cast<float>(target_resolution.width) / src.nx;
            float scale_h = static_cast<float>(target_resolution.height) / src.ny;
            float scale = std::min(scale_w, scale_h);
            int new_width  = std::min(static_cast<int>(std::ceil(src.nx * scale)), target_resolution.width);
            int new_height = std::min(static_cast<int>(std::ceil(src.ny * scale)), target_resolution.height);

            switch (algo) {
                case RESIZE_ALGO_BILINEAR:
                    resize_bilinear(src, resized_image, new_width, new_height);
                    break;
                case RESIZE_ALGO_BICUBIC:
                    resize_bicubic(src, resized_image, new_width, new_height);
                    break;
                default:
                    throw std::runtime_error("Unsupported resize algorithm");
            }

            // fill dst with pad_color
            fill(dst, pad_color);

            int offset_x = (target_resolution.width  - new_width)  / 2;
            int offset_y = (target_resolution.height - new_height) / 2;

            composite(dst, resized_image, offset_x, offset_y);
        }
    }