chamelium: Add support for VGA frame comparison testing

This adds support for VGA frame comparison testing with the reference
generated from cairo. The retrieved frame from the chamelium is first
cropped, as it contains the blanking intervals, through a dedicated
helper. Another helper function asserts that the analog frame
matches or dump it to png if not.

Signed-off-by: Paul Kocialkowski <paul.kocialkowski@linux.intel.com>
Reviewed-by: Lyude <lyude@redhat.com>

1 files changed, 159 insertions, 5 deletions

diff --git a/lib/igt_chamelium.c b/lib/igt_chamelium.c
index 348d2176..dcd8855f 100644
--- a/lib/igt_chamelium.c
+++ b/lib/igt_chamelium.c
@@ -937,6 +937,8 @@ static cairo_surface_t *convert_frame_dump_argb32(const struct chamelium_frame_d
 	int w = dump->width, h = dump->height;
 	uint32_t *bits_bgr = (uint32_t *) dump->bgr;
 	unsigned char *bits_argb;
+	unsigned char *bits_target;
+	int size;
 
 	image_bgr = pixman_image_create_bits(
 	    PIXMAN_b8g8r8, w, h, bits_bgr,
@@ -946,9 +948,13 @@ static cairo_surface_t *convert_frame_dump_argb32(const struct chamelium_frame_d
 
 	bits_argb = (unsigned char *) pixman_image_get_data(image_argb);
 
-	dump_surface = cairo_image_surface_create_for_data(
-	    bits_argb, CAIRO_FORMAT_ARGB32, w, h,
-	    PIXMAN_FORMAT_BPP(PIXMAN_x8r8g8b8) / 8 * w);
+	dump_surface = cairo_image_surface_create(
+	    CAIRO_FORMAT_ARGB32, w, h);
+
+	bits_target = cairo_image_surface_get_data(dump_surface);
+	size = cairo_image_surface_get_stride(dump_surface) * h;
+	memcpy(bits_target, bits_argb, size);
+	cairo_surface_mark_dirty(dump_surface);
 
 	pixman_image_unref(image_argb);
 
@@ -1054,6 +1060,154 @@ void chamelium_assert_crc_eq_or_dump(struct chamelium *chamelium,
 }
 
 /**
+ * chamelium_assert_analog_frame_match_or_dump:
+ * @chamelium: The chamelium instance the frame dump belongs to
+ * @frame: The chamelium frame dump to match
+ * @fb: pointer to an #igt_fb structure
+ *
+ * Asserts that the provided captured frame matches the reference frame from
+ * the framebuffer. If they do not, this saves the reference and captured frames
+ * to a png file.
+ */
+void chamelium_assert_analog_frame_match_or_dump(struct chamelium *chamelium,
+						 struct chamelium_port *port,
+						 const struct chamelium_frame_dump *frame,
+						 struct igt_fb *fb)
+{
+	cairo_surface_t *reference;
+	cairo_surface_t *capture;
+	igt_crc_t *reference_crc;
+	igt_crc_t *capture_crc;
+	char *reference_suffix;
+	char *capture_suffix;
+	bool match;
+
+	/* Grab the reference frame from framebuffer */
+	reference = igt_get_cairo_surface(chamelium->drm_fd, fb);
+
+	/* Grab the captured frame from chamelium */
+	capture = convert_frame_dump_argb32(frame);
+
+	match = igt_check_analog_frame_match(reference, capture);
+	if (!match && igt_frame_dump_is_enabled()) {
+		reference_crc = chamelium_calculate_fb_crc(chamelium->drm_fd,
+							   fb);
+		capture_crc = chamelium_get_crc_for_area(chamelium, port, 0, 0,
+							 0, 0);
+
+		reference_suffix = igt_crc_to_string_extended(reference_crc,
+							      '-', 2);
+		capture_suffix = igt_crc_to_string_extended(capture_crc, '-',
+							    2);
+
+		/* Write reference and capture frames to png */
+		igt_write_compared_frames_to_png(reference, capture,
+						 reference_suffix,
+						 capture_suffix);
+
+		free(reference_suffix);
+		free(capture_suffix);
+	}
+
+	cairo_surface_destroy(capture);
+
+	igt_assert(match);
+}
+
+
+/**
+ * chamelium_analog_frame_crop:
+ * @chamelium: The Chamelium instance to use
+ * @dump: The chamelium frame dump to crop
+ * @width: The cropped frame width
+ * @height: The cropped frame height
+ *
+ * Detects the corners of a chamelium frame and crops it to the requested
+ * width/height. This is useful for VGA frame dumps that also contain the
+ * pixels dumped during the blanking intervals.
+ *
+ * The detection is done on a brightness-threshold-basis, that is adapted
+ * to the reference frame used by i-g-t. It may not be as relevant for other
+ * frames.
+ */
+void chamelium_crop_analog_frame(struct chamelium_frame_dump *dump, int width,
+				 int height)
+{
+	unsigned char *bgr;
+	unsigned char *p;
+	unsigned char *q;
+	int top, left;
+	int x, y, xx, yy;
+	int score;
+
+	if (dump->width == width && dump->height == height)
+		return;
+
+	/* Start with the most bottom-right position. */
+	top = dump->height - height;
+	left = dump->width - width;
+
+	igt_assert(top >= 0 && left >= 0);
+
+	igt_debug("Cropping analog frame from %dx%d to %dx%d\n", dump->width,
+		  dump->height, width, height);
+
+	/* Detect the top-left corner of the frame. */
+	for (x = 0; x < dump->width; x++) {
+		for (y = 0; y < dump->height; y++) {
+			p = &dump->bgr[(x + y * dump->width) * 3];
+
+			/* Detect significantly bright pixels. */
+			if (p[0] < 50 && p[1] < 50 && p[2] < 50)
+				continue;
+
+			/*
+			 * Make sure close-by pixels are also significantly
+			 * bright.
+			 */
+			score = 0;
+			for (xx = x; xx < x + 10; xx++) {
+				for (yy = y; yy < y + 10; yy++) {
+					p = &dump->bgr[(xx + yy * dump->width) * 3];
+
+					if (p[0] > 50 && p[1] > 50 && p[2] > 50)
+						score++;
+				}
+			}
+
+			/* Not enough pixels are significantly bright. */
+			if (score < 25)
+				continue;
+
+			if (x < left)
+				left = x;
+
+			if (y < top)
+				top = y;
+
+			if (left == x || top == y)
+				continue;
+		}
+	}
+
+	igt_debug("Detected analog frame edges at %dx%d\n", left, top);
+
+	/* Crop the frame given the detected top-left corner. */
+	bgr = malloc(width * height * 3);
+
+	for (y = 0; y < height; y++) {
+		p = &dump->bgr[(left + (top + y) * dump->width) * 3];
+		q = &bgr[(y * width) * 3];
+		memcpy(q, p, width * 3);
+	}
+
+	free(dump->bgr);
+	dump->width = width;
+	dump->height = height;
+	dump->bgr = bgr;
+}
+
+/**
  * chamelium_get_frame_limit:
  * @chamelium: The Chamelium instance to use
  * @port: The port to check the frame limit on
@@ -1480,7 +1634,7 @@ igt_constructor {
 	/* Frame dumps can be large, so we need to be able to handle very large
 	 * responses
 	 *
-	 * Limit here is 10MB
+	 * Limit here is 15MB
 	 */
-	xmlrpc_limit_set(XMLRPC_XML_SIZE_LIMIT_ID, 10485760);
+	xmlrpc_limit_set(XMLRPC_XML_SIZE_LIMIT_ID, 15728640);
 }