video: fix missing crop/compose handling in capture_to_lvgl sample & add missing conf files for stm32n657 fsbl variant

boards/shields/st_b_cams_imx_mb1854/Kconfig.defconfig

@@ -0,0 +1,17 @@
+# ST_B_CAMS_IMX_MB1854 configuration
+
+# Copyright (c) 2025 STMicroelectronics
+# SPDX-License-Identifier: Apache-2.0
+
+if VIDEO_STM32_DCMIPP
+
+config VIDEO_STM32_DCMIPP_SENSOR_PIXEL_FORMAT
+	default "pRAA"
+
+config VIDEO_STM32_DCMIPP_SENSOR_WIDTH
+	default 2592
+
+config VIDEO_STM32_DCMIPP_SENSOR_HEIGHT
+	default 1944
+
+endif # VIDEO_STM32_DCMIPP

samples/drivers/video/capture/boards/stm32n6570_dk_stm32n657xx_fsbl.conf

@@ -0,0 +1,6 @@
+CONFIG_VIDEO_FRAME_WIDTH=800
+CONFIG_VIDEO_FRAME_HEIGHT=480
+CONFIG_VIDEO_PIXEL_FORMAT="RGBP"
+CONFIG_VIDEO_BUFFER_POOL_SZ_MAX=800000
+CONFIG_VIDEO_BUFFER_POOL_NUM_MAX=2
+CONFIG_MAIN_STACK_SIZE=2048

samples/drivers/video/capture_to_lvgl/Kconfig

@@ -7,6 +7,32 @@ mainmenu "Video capture to LVGL sample application"
 
 menu "Video capture configuration"
 
+config VIDEO_SOURCE_CROP_LEFT
+	int "Crop area left value"
+	default 0
+	help
+	   Left value of the crop area within the video source.
+
+config VIDEO_SOURCE_CROP_TOP
+	int "Crop area top value"
+	default 0
+	help
+	   Top value of the crop area within the video source.
+
+config VIDEO_SOURCE_CROP_WIDTH
+	int "Crop area width value"
+	default 0
+	help
+	   Width value of the crop area within the video source.
+	   If set to 0, the crop is not applied.
+
+config VIDEO_SOURCE_CROP_HEIGHT
+	int "Crop area height value"
+	default 0
+	help
+	   Height value of the crop area within the video source.
+	   If set to 0, the crop is not applied.
+
 config VIDEO_WIDTH
 	int "Define the width of the video"
 	default 320

samples/drivers/video/capture_to_lvgl/boards/stm32n6570_dk_stm32n657xx_fsbl.conf

@@ -0,0 +1,5 @@
+CONFIG_VIDEO_WIDTH=800
+CONFIG_VIDEO_HEIGHT=480
+CONFIG_VIDEO_BUFFER_POOL_SZ_MAX=800000
+CONFIG_VIDEO_BUFFER_POOL_NUM_MAX=2
+CONFIG_MAIN_STACK_SIZE=4096

samples/drivers/video/capture_to_lvgl/src/main.c

@@ -23,8 +23,12 @@ int main(void)
 	struct video_format fmt;
 	struct video_caps caps;
 	enum video_buf_type type = VIDEO_BUF_TYPE_OUTPUT;
+	struct video_selection sel = {
+		.type = VIDEO_BUF_TYPE_OUTPUT,
+	};
 	size_t bsize;
 	int i = 0;
+	int err;
 
 	display_dev = DEVICE_DT_GET(DT_CHOSEN(zephyr_display));
 	if (!device_is_ready(display_dev)) {
@@ -66,11 +70,50 @@ int main(void)
 		return 0;
 	}
 
+	/* Set the crop setting if necessary */
+#if CONFIG_VIDEO_SOURCE_CROP_WIDTH && CONFIG_VIDEO_SOURCE_CROP_HEIGHT
+	sel.target = VIDEO_SEL_TGT_CROP;
+	sel.rect.left = CONFIG_VIDEO_SOURCE_CROP_LEFT;
+	sel.rect.top = CONFIG_VIDEO_SOURCE_CROP_TOP;
+	sel.rect.width = CONFIG_VIDEO_SOURCE_CROP_WIDTH;
+	sel.rect.height = CONFIG_VIDEO_SOURCE_CROP_HEIGHT;
+	if (video_set_selection(video_dev, &sel)) {
+		LOG_ERR("Unable to set selection crop");
+		return 0;
+	}
+	LOG_INF("Selection crop set to (%u,%u)/%ux%u",
+		sel.rect.left, sel.rect.top, sel.rect.width, sel.rect.height);
+#endif
+
 	/* Set format */
 	fmt.width = CONFIG_VIDEO_WIDTH;
 	fmt.height = CONFIG_VIDEO_HEIGHT;
 	fmt.pixelformat = VIDEO_PIX_FMT_RGB565;
 
+	/*
+	 * Check (if possible) if targeted size is same as crop
+	 * and if compose is necessary
+	 */
+	sel.target = VIDEO_SEL_TGT_CROP;
+	err = video_get_selection(video_dev, &sel);
+	if (err < 0 && err != -ENOSYS) {
+		LOG_ERR("Unable to get selection crop");
+		return 0;
+	}
+
+	if (err == 0 && (sel.rect.width != fmt.width || sel.rect.height != fmt.height)) {
+		sel.target = VIDEO_SEL_TGT_COMPOSE;
+		sel.rect.left = 0;
+		sel.rect.top = 0;
+		sel.rect.width = fmt.width;
+		sel.rect.height = fmt.height;
+		err = video_set_selection(video_dev, &sel);
+		if (err < 0 && err != -ENOSYS) {
+			LOG_ERR("Unable to set selection compose");
+			return 0;
+		}
+	}
+
 	if (video_set_format(video_dev, &fmt)) {
 		LOG_ERR("Unable to set up video format");
 		return 0;
@@ -134,8 +177,6 @@ int main(void)
 	/* Grab video frames */
 	vbuf->type = type;
 	while (1) {
-		int err;
-
 		err = video_dequeue(video_dev, &vbuf, K_FOREVER);
 		if (err) {
 			LOG_ERR("Unable to dequeue video buf");