X-Git-Url: https://git.ao2.it/libam7xxx.git/blobdiff_plain/a09eb6616f4c6c67d4de4c8b72d9072f787ad2de..b19775ece86f40df15ffadcb358c8896bc847482:/src/am7xxx.c diff --git a/src/am7xxx.c b/src/am7xxx.c index 48704de..a8bcc49 100644 --- a/src/am7xxx.c +++ b/src/am7xxx.c @@ -445,7 +445,7 @@ typedef enum { * device with index 'open_device_index' and returns the correspondent * am7xxx_device in the 'dev' parameter; the function returns 0 on success, * 1 if the device was already open and a negative value on error. - * + * * NOTES: * if scan_devices() fails when called with 'op' == SCAN_OP_BUILD_DEVLIST, * the caller might want to call am7xxx_shutdown() in order to remove @@ -690,12 +690,74 @@ int am7xxx_get_device_info(am7xxx_device *dev, return 0; } +int am7xxx_calc_scaled_image_dimensions(am7xxx_device *dev, + unsigned int upscale, + unsigned int original_width, + unsigned int original_height, + unsigned int *scaled_width, + unsigned int *scaled_height) +{ + + am7xxx_device_info device_info; + float width_ratio; + float height_ratio; + int ret; + + ret = am7xxx_get_device_info(dev, &device_info); + if (ret < 0) { + error(dev->ctx, "cannot get device info\n"); + return ret; + } + + /* + * Check if we need to rescale; if the input image fits the native + * dimensions there is no need to, unless we want to upscale. + */ + if (!upscale && + original_width <= device_info.native_width && + original_height <= device_info.native_height ) { + debug(dev->ctx, "CASE 0, no rescaling, the original image fits already\n"); + *scaled_width = original_width; + *scaled_height = original_height; + return 0; + } + + /* Input dimensions relative to the device native dimensions */ + width_ratio = (float)original_width / device_info.native_width; + height_ratio = (float)original_height / device_info.native_height; + + if (width_ratio > height_ratio) { + /* + * The input is proportionally "wider" than the device viewport + * so its height needs to be adjusted + */ + debug(dev->ctx, "CASE 1, original image wider, adjust the scaled height\n"); + *scaled_width = device_info.native_width; + *scaled_height = (unsigned int)(original_height / width_ratio); + } else if (width_ratio < height_ratio) { + /* + * The input is proportionally "taller" than the device viewport + * so its width needs to be adjusted + */ + debug(dev->ctx, "CASE 2 original image taller, adjust the scaled width\n"); + *scaled_width = (unsigned int)(original_width / height_ratio); + *scaled_height = device_info.native_height; + } else { + debug(dev->ctx, "CASE 3, just rescale, same aspect ratio already\n"); + *scaled_width = device_info.native_width; + *scaled_height = device_info.native_height; + } + debug(dev->ctx, "scaled dimensions: %dx%d\n", *scaled_width, *scaled_height); + + return 0; +} + int am7xxx_send_image(am7xxx_device *dev, am7xxx_image_format format, unsigned int width, unsigned int height, uint8_t *image, - unsigned int size) + unsigned int image_size) { int ret; struct am7xxx_header h = { @@ -709,7 +771,7 @@ int am7xxx_send_image(am7xxx_device *dev, .format = format, .width = width, .height = height, - .image_size = size, + .image_size = image_size, }, }, }; @@ -718,12 +780,12 @@ int am7xxx_send_image(am7xxx_device *dev, if (ret < 0) return ret; - if (image == NULL || size == 0) { - warning(dev->ctx, "Not sending any data, check the 'data' or 'size' parameters\n"); + if (image == NULL || image_size == 0) { + warning(dev->ctx, "Not sending any data, check the 'image' or 'image_size' parameters\n"); return 0; } - return send_data(dev, image, size); + return send_data(dev, image, image_size); } int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode mode)