[PATCH 12/18] [media] cx2341x: add contents of README.hm12

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The README.hm12 file describes the proprietary format used
by this driver for raw format, called HM12. Add its description
at the document, after converted to ReST.

Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
---
 Documentation/media/v4l-drivers/cx2341x.rst   | 125 ++++++++++++++++++++++++++
 Documentation/video4linux/cx2341x/README.hm12 | 120 -------------------------
 2 files changed, 125 insertions(+), 120 deletions(-)
 delete mode 100644 Documentation/video4linux/cx2341x/README.hm12

diff --git a/Documentation/media/v4l-drivers/cx2341x.rst b/Documentation/media/v4l-drivers/cx2341x.rst
index 57ae45938919..15bfd345df48 100644
--- a/Documentation/media/v4l-drivers/cx2341x.rst
+++ b/Documentation/media/v4l-drivers/cx2341x.rst
@@ -3681,3 +3681,128 @@ Register 0x0004 holds the DMA Transfer Status:
 - bit 2:   DMA read error
 - bit 3:   DMA write error
 - bit 4:   Scatter-Gather array error
+
+Non-compressed file format
+--------------------------
+
+The cx23416 can produce (and the cx23415 can also read) raw YUV output. The
+format of a YUV frame is specific to this chip and is called HM12. 'HM' stands
+for 'Hauppauge Macroblock', which is a misnomer as 'Conexant Macroblock' would
+be more accurate.
+
+The format is YUV 4:2:0 which uses 1 Y byte per pixel and 1 U and V byte per
+four pixels.
+
+The data is encoded as two macroblock planes, the first containing the Y
+values, the second containing UV macroblocks.
+
+The Y plane is divided into blocks of 16x16 pixels from left to right
+and from top to bottom. Each block is transmitted in turn, line-by-line.
+
+So the first 16 bytes are the first line of the top-left block, the
+second 16 bytes are the second line of the top-left block, etc. After
+transmitting this block the first line of the block on the right to the
+first block is transmitted, etc.
+
+The UV plane is divided into blocks of 16x8 UV values going from left
+to right, top to bottom. Each block is transmitted in turn, line-by-line.
+
+So the first 16 bytes are the first line of the top-left block and
+contain 8 UV value pairs (16 bytes in total). The second 16 bytes are the
+second line of 8 UV pairs of the top-left block, etc. After transmitting
+this block the first line of the block on the right to the first block is
+transmitted, etc.
+
+The code below is given as an example on how to convert HM12 to separate
+Y, U and V planes. This code assumes frames of 720x576 (PAL) pixels.
+
+The width of a frame is always 720 pixels, regardless of the actual specified
+width.
+
+If the height is not a multiple of 32 lines, then the captured video is
+missing macroblocks at the end and is unusable. So the height must be a
+multiple of 32.
+
+Raw format c example
+~~~~~~~~~~~~~~~~~~~~
+
+.. code-block:: c
+
+	#include <stdio.h>
+	#include <stdlib.h>
+	#include <string.h>
+
+	static unsigned char frame[576*720*3/2];
+	static unsigned char framey[576*720];
+	static unsigned char frameu[576*720 / 4];
+	static unsigned char framev[576*720 / 4];
+
+	static void de_macro_y(unsigned char* dst, unsigned char *src, int dstride, int w, int h)
+	{
+	unsigned int y, x, i;
+
+	// descramble Y plane
+	// dstride = 720 = w
+	// The Y plane is divided into blocks of 16x16 pixels
+	// Each block in transmitted in turn, line-by-line.
+	for (y = 0; y < h; y += 16) {
+		for (x = 0; x < w; x += 16) {
+		for (i = 0; i < 16; i++) {
+			memcpy(dst + x + (y + i) * dstride, src, 16);
+			src += 16;
+		}
+		}
+	}
+	}
+
+	static void de_macro_uv(unsigned char *dstu, unsigned char *dstv, unsigned char *src, int dstride, int w, int h)
+	{
+	unsigned int y, x, i;
+
+	// descramble U/V plane
+	// dstride = 720 / 2 = w
+	// The U/V values are interlaced (UVUV...).
+	// Again, the UV plane is divided into blocks of 16x16 UV values.
+	// Each block in transmitted in turn, line-by-line.
+	for (y = 0; y < h; y += 16) {
+		for (x = 0; x < w; x += 8) {
+		for (i = 0; i < 16; i++) {
+			int idx = x + (y + i) * dstride;
+
+			dstu[idx+0] = src[0];  dstv[idx+0] = src[1];
+			dstu[idx+1] = src[2];  dstv[idx+1] = src[3];
+			dstu[idx+2] = src[4];  dstv[idx+2] = src[5];
+			dstu[idx+3] = src[6];  dstv[idx+3] = src[7];
+			dstu[idx+4] = src[8];  dstv[idx+4] = src[9];
+			dstu[idx+5] = src[10]; dstv[idx+5] = src[11];
+			dstu[idx+6] = src[12]; dstv[idx+6] = src[13];
+			dstu[idx+7] = src[14]; dstv[idx+7] = src[15];
+			src += 16;
+		}
+		}
+	}
+	}
+
+	/*************************************************************************/
+	int main(int argc, char **argv)
+	{
+	FILE *fin;
+	int i;
+
+	if (argc == 1) fin = stdin;
+	else fin = fopen(argv[1], "r");
+
+	if (fin == NULL) {
+		fprintf(stderr, "cannot open input\n");
+		exit(-1);
+	}
+	while (fread(frame, sizeof(frame), 1, fin) == 1) {
+		de_macro_y(framey, frame, 720, 720, 576);
+		de_macro_uv(frameu, framev, frame + 720 * 576, 720 / 2, 720 / 2, 576 / 2);
+		fwrite(framey, sizeof(framey), 1, stdout);
+		fwrite(framev, sizeof(framev), 1, stdout);
+		fwrite(frameu, sizeof(frameu), 1, stdout);
+	}
+	fclose(fin);
+	return 0;
+	}
diff --git a/Documentation/video4linux/cx2341x/README.hm12 b/Documentation/video4linux/cx2341x/README.hm12
deleted file mode 100644
index b36148ea0750..000000000000
--- a/Documentation/video4linux/cx2341x/README.hm12
+++ /dev/null
@@ -1,120 +0,0 @@
-The cx23416 can produce (and the cx23415 can also read) raw YUV output. The
-format of a YUV frame is specific to this chip and is called HM12. 'HM' stands
-for 'Hauppauge Macroblock', which is a misnomer as 'Conexant Macroblock' would
-be more accurate.
-
-The format is YUV 4:2:0 which uses 1 Y byte per pixel and 1 U and V byte per
-four pixels.
-
-The data is encoded as two macroblock planes, the first containing the Y
-values, the second containing UV macroblocks.
-
-The Y plane is divided into blocks of 16x16 pixels from left to right
-and from top to bottom. Each block is transmitted in turn, line-by-line.
-
-So the first 16 bytes are the first line of the top-left block, the
-second 16 bytes are the second line of the top-left block, etc. After
-transmitting this block the first line of the block on the right to the
-first block is transmitted, etc.
-
-The UV plane is divided into blocks of 16x8 UV values going from left
-to right, top to bottom. Each block is transmitted in turn, line-by-line.
-
-So the first 16 bytes are the first line of the top-left block and
-contain 8 UV value pairs (16 bytes in total). The second 16 bytes are the
-second line of 8 UV pairs of the top-left block, etc. After transmitting
-this block the first line of the block on the right to the first block is
-transmitted, etc.
-
-The code below is given as an example on how to convert HM12 to separate
-Y, U and V planes. This code assumes frames of 720x576 (PAL) pixels.
-
-The width of a frame is always 720 pixels, regardless of the actual specified
-width.
-
-If the height is not a multiple of 32 lines, then the captured video is
-missing macroblocks at the end and is unusable. So the height must be a
-multiple of 32.
-
---------------------------------------------------------------------------
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-static unsigned char frame[576*720*3/2];
-static unsigned char framey[576*720];
-static unsigned char frameu[576*720 / 4];
-static unsigned char framev[576*720 / 4];
-
-static void de_macro_y(unsigned char* dst, unsigned char *src, int dstride, int w, int h)
-{
-    unsigned int y, x, i;
-
-    // descramble Y plane
-    // dstride = 720 = w
-    // The Y plane is divided into blocks of 16x16 pixels
-    // Each block in transmitted in turn, line-by-line.
-    for (y = 0; y < h; y += 16) {
-	for (x = 0; x < w; x += 16) {
-	    for (i = 0; i < 16; i++) {
-		memcpy(dst + x + (y + i) * dstride, src, 16);
-		src += 16;
-	    }
-	}
-    }
-}
-
-static void de_macro_uv(unsigned char *dstu, unsigned char *dstv, unsigned char *src, int dstride, int w, int h)
-{
-    unsigned int y, x, i;
-
-    // descramble U/V plane
-    // dstride = 720 / 2 = w
-    // The U/V values are interlaced (UVUV...).
-    // Again, the UV plane is divided into blocks of 16x16 UV values.
-    // Each block in transmitted in turn, line-by-line.
-    for (y = 0; y < h; y += 16) {
-	for (x = 0; x < w; x += 8) {
-	    for (i = 0; i < 16; i++) {
-		int idx = x + (y + i) * dstride;
-
-		dstu[idx+0] = src[0];  dstv[idx+0] = src[1];
-		dstu[idx+1] = src[2];  dstv[idx+1] = src[3];
-		dstu[idx+2] = src[4];  dstv[idx+2] = src[5];
-		dstu[idx+3] = src[6];  dstv[idx+3] = src[7];
-		dstu[idx+4] = src[8];  dstv[idx+4] = src[9];
-		dstu[idx+5] = src[10]; dstv[idx+5] = src[11];
-		dstu[idx+6] = src[12]; dstv[idx+6] = src[13];
-		dstu[idx+7] = src[14]; dstv[idx+7] = src[15];
-		src += 16;
-	    }
-	}
-    }
-}
-
-/*************************************************************************/
-int main(int argc, char **argv)
-{
-    FILE *fin;
-    int i;
-
-    if (argc == 1) fin = stdin;
-    else fin = fopen(argv[1], "r");
-
-    if (fin == NULL) {
-	fprintf(stderr, "cannot open input\n");
-	exit(-1);
-    }
-    while (fread(frame, sizeof(frame), 1, fin) == 1) {
-	de_macro_y(framey, frame, 720, 720, 576);
-	de_macro_uv(frameu, framev, frame + 720 * 576, 720 / 2, 720 / 2, 576 / 2);
-	fwrite(framey, sizeof(framey), 1, stdout);
-	fwrite(framev, sizeof(framev), 1, stdout);
-	fwrite(frameu, sizeof(frameu), 1, stdout);
-    }
-    fclose(fin);
-    return 0;
-}
-
---------------------------------------------------------------------------
-- 
2.7.4


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