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Based on kernel version 3.16. Page generated on 2014-08-06 21:38 EST.

1	  <title>Image Formats</title>
2	
3	  <para>The V4L2 API was primarily designed for devices exchanging
4	image data with applications. The
5	<structname>v4l2_pix_format</structname> and <structname>v4l2_pix_format_mplane
6	</structname> structures define the format and layout of an image in memory.
7	The former is used with the single-planar API, while the latter is used with the
8	multi-planar version (see <xref linkend="planar-apis"/>). Image formats are
9	negotiated with the &VIDIOC-S-FMT; ioctl. (The explanations here focus on video
10	capturing and output, for overlay frame buffer formats see also
11	&VIDIOC-G-FBUF;.)</para>
12	
13	<section>
14	  <title>Single-planar format structure</title>
15	  <table pgwide="1" frame="none" id="v4l2-pix-format">
16	    <title>struct <structname>v4l2_pix_format</structname></title>
17	    <tgroup cols="3">
18	      &cs-str;
19	      <tbody valign="top">
20		<row>
21		  <entry>__u32</entry>
22		  <entry><structfield>width</structfield></entry>
23		  <entry>Image width in pixels.</entry>
24		</row>
25		<row>
26		  <entry>__u32</entry>
27		  <entry><structfield>height</structfield></entry>
28		  <entry>Image height in pixels. If <structfield>field</structfield> is
29		  one of <constant>V4L2_FIELD_TOP</constant>, <constant>V4L2_FIELD_BOTTOM</constant>
30		  or <constant>V4L2_FIELD_ALTERNATE</constant> then height refers to the
31		  number of lines in the field, otherwise it refers to the number of
32		  lines in the frame (which is twice the field height for interlaced
33		  formats).</entry>
34		</row>
35		<row>
36		  <entry spanname="hspan">Applications set these fields to
37	request an image size, drivers return the closest possible values. In
38	case of planar formats the <structfield>width</structfield> and
39	<structfield>height</structfield> applies to the largest plane. To
40	avoid ambiguities drivers must return values rounded up to a multiple
41	of the scale factor of any smaller planes. For example when the image
42	format is YUV 4:2:0, <structfield>width</structfield> and
43	<structfield>height</structfield> must be multiples of two.</entry>
44		</row>
45		<row>
46		  <entry>__u32</entry>
47		  <entry><structfield>pixelformat</structfield></entry>
48		  <entry>The pixel format or type of compression, set by the
49	application. This is a little endian <link
50	linkend="v4l2-fourcc">four character code</link>. V4L2 defines
51	standard RGB formats in <xref linkend="rgb-formats" />, YUV formats in <xref
52	linkend="yuv-formats" />, and reserved codes in <xref
53	linkend="reserved-formats" /></entry>
54		</row>
55		<row>
56		  <entry>&v4l2-field;</entry>
57		  <entry><structfield>field</structfield></entry>
58		  <entry>Video images are typically interlaced. Applications
59	can request to capture or output only the top or bottom field, or both
60	fields interlaced or sequentially stored in one buffer or alternating
61	in separate buffers. Drivers return the actual field order selected.
62	For more details on fields see <xref linkend="field-order" />.</entry>
63		</row>
64		<row>
65		  <entry>__u32</entry>
66		  <entry><structfield>bytesperline</structfield></entry>
67		  <entry>Distance in bytes between the leftmost pixels in two
68	adjacent lines.</entry>
69		</row>
70		<row>
71		  <entry spanname="hspan"><para>Both applications and drivers
72	can set this field to request padding bytes at the end of each line.
73	Drivers however may ignore the value requested by the application,
74	returning <structfield>width</structfield> times bytes per pixel or a
75	larger value required by the hardware. That implies applications can
76	just set this field to zero to get a reasonable
77	default.</para><para>Video hardware may access padding bytes,
78	therefore they must reside in accessible memory. Consider cases where
79	padding bytes after the last line of an image cross a system page
80	boundary. Input devices may write padding bytes, the value is
81	undefined. Output devices ignore the contents of padding
82	bytes.</para><para>When the image format is planar the
83	<structfield>bytesperline</structfield> value applies to the largest
84	plane and is divided by the same factor as the
85	<structfield>width</structfield> field for any smaller planes. For
86	example the Cb and Cr planes of a YUV 4:2:0 image have half as many
87	padding bytes following each line as the Y plane. To avoid ambiguities
88	drivers must return a <structfield>bytesperline</structfield> value
89	rounded up to a multiple of the scale factor.</para>
90	<para>For compressed formats the <structfield>bytesperline</structfield>
91	value makes no sense. Applications and drivers must set this to 0 in
92	that case.</para></entry>
93		</row>
94		<row>
95		  <entry>__u32</entry>
96		  <entry><structfield>sizeimage</structfield></entry>
97		  <entry>Size in bytes of the buffer to hold a complete image,
98	set by the driver. Usually this is
99	<structfield>bytesperline</structfield> times
100	<structfield>height</structfield>. When the image consists of variable
101	length compressed data this is the maximum number of bytes required to
102	hold an image.</entry>
103		</row>
104		<row>
105		  <entry>&v4l2-colorspace;</entry>
106		  <entry><structfield>colorspace</structfield></entry>
107		  <entry>This information supplements the
108	<structfield>pixelformat</structfield> and must be set by the driver for
109	capture streams and by the application for output streams,
110	see <xref linkend="colorspaces" />.</entry>
111		</row>
112		<row>
113		  <entry>__u32</entry>
114		  <entry><structfield>priv</structfield></entry>
115		  <entry>Reserved for custom (driver defined) additional
116	information about formats. When not used drivers and applications must
117	set this field to zero.</entry>
118		</row>
119	      </tbody>
120	    </tgroup>
121	  </table>
122	</section>
123	
124	<section>
125	  <title>Multi-planar format structures</title>
126	  <para>The <structname>v4l2_plane_pix_format</structname> structures define
127	    size and layout for each of the planes in a multi-planar format.
128	    The <structname>v4l2_pix_format_mplane</structname> structure contains
129	    information common to all planes (such as image width and height) and
130	    an array of <structname>v4l2_plane_pix_format</structname> structures,
131	    describing all planes of that format.</para>
132	  <table pgwide="1" frame="none" id="v4l2-plane-pix-format">
133	    <title>struct <structname>v4l2_plane_pix_format</structname></title>
134	    <tgroup cols="3">
135	      &cs-str;
136	      <tbody valign="top">
137	        <row>
138	          <entry>__u32</entry>
139	          <entry><structfield>sizeimage</structfield></entry>
140	          <entry>Maximum size in bytes required for image data in this plane.
141	          </entry>
142	        </row>
143	        <row>
144	          <entry>__u16</entry>
145	          <entry><structfield>bytesperline</structfield></entry>
146	          <entry>Distance in bytes between the leftmost pixels in two adjacent
147	            lines. See &v4l2-pix-format;.</entry>
148	        </row>
149	        <row>
150	          <entry>__u16</entry>
151	          <entry><structfield>reserved[7]</structfield></entry>
152	          <entry>Reserved for future extensions. Should be zeroed by the
153	           application.</entry>
154	        </row>
155	      </tbody>
156	    </tgroup>
157	  </table>
158	  <table pgwide="1" frame="none" id="v4l2-pix-format-mplane">
159	    <title>struct <structname>v4l2_pix_format_mplane</structname></title>
160	    <tgroup cols="3">
161	      &cs-str;
162	      <tbody valign="top">
163	        <row>
164	          <entry>__u32</entry>
165	          <entry><structfield>width</structfield></entry>
166	          <entry>Image width in pixels. See &v4l2-pix-format;.</entry>
167	        </row>
168	        <row>
169	          <entry>__u32</entry>
170	          <entry><structfield>height</structfield></entry>
171	          <entry>Image height in pixels. See &v4l2-pix-format;.</entry>
172	        </row>
173	        <row>
174	          <entry>__u32</entry>
175	          <entry><structfield>pixelformat</structfield></entry>
176	          <entry>The pixel format. Both single- and multi-planar four character
177	codes can be used.</entry>
178	        </row>
179	        <row>
180	          <entry>&v4l2-field;</entry>
181	          <entry><structfield>field</structfield></entry>
182	          <entry>See &v4l2-pix-format;.</entry>
183	        </row>
184	        <row>
185	          <entry>&v4l2-colorspace;</entry>
186	          <entry><structfield>colorspace</structfield></entry>
187	          <entry>See &v4l2-pix-format;.</entry>
188	        </row>
189	        <row>
190	          <entry>&v4l2-plane-pix-format;</entry>
191	          <entry><structfield>plane_fmt[VIDEO_MAX_PLANES]</structfield></entry>
192	          <entry>An array of structures describing format of each plane this
193	          pixel format consists of. The number of valid entries in this array
194	          has to be put in the <structfield>num_planes</structfield>
195	          field.</entry>
196	        </row>
197	        <row>
198	          <entry>__u8</entry>
199	          <entry><structfield>num_planes</structfield></entry>
200	          <entry>Number of planes (i.e. separate memory buffers) for this format
201	          and the number of valid entries in the
202	          <structfield>plane_fmt</structfield> array.</entry>
203	        </row>
204	        <row>
205	          <entry>__u8</entry>
206	          <entry><structfield>reserved[11]</structfield></entry>
207	          <entry>Reserved for future extensions. Should be zeroed by the
208	           application.</entry>
209	        </row>
210	      </tbody>
211	    </tgroup>
212	  </table>
213	</section>
214	
215	  <section>
216	    <title>Standard Image Formats</title>
217	
218	    <para>In order to exchange images between drivers and
219	applications, it is necessary to have standard image data formats
220	which both sides will interpret the same way. V4L2 includes several
221	such formats, and this section is intended to be an unambiguous
222	specification of the standard image data formats in V4L2.</para>
223	
224	    <para>V4L2 drivers are not limited to these formats, however.
225	Driver-specific formats are possible. In that case the application may
226	depend on a codec to convert images to one of the standard formats
227	when needed. But the data can still be stored and retrieved in the
228	proprietary format. For example, a device may support a proprietary
229	compressed format. Applications can still capture and save the data in
230	the compressed format, saving much disk space, and later use a codec
231	to convert the images to the X Windows screen format when the video is
232	to be displayed.</para>
233	
234	    <para>Even so, ultimately, some standard formats are needed, so
235	the V4L2 specification would not be complete without well-defined
236	standard formats.</para>
237	
238	    <para>The V4L2 standard formats are mainly uncompressed formats. The
239	pixels are always arranged in memory from left to right, and from top
240	to bottom. The first byte of data in the image buffer is always for
241	the leftmost pixel of the topmost row. Following that is the pixel
242	immediately to its right, and so on until the end of the top row of
243	pixels. Following the rightmost pixel of the row there may be zero or
244	more bytes of padding to guarantee that each row of pixel data has a
245	certain alignment. Following the pad bytes, if any, is data for the
246	leftmost pixel of the second row from the top, and so on. The last row
247	has just as many pad bytes after it as the other rows.</para>
248	
249	    <para>In V4L2 each format has an identifier which looks like
250	<constant>PIX_FMT_XXX</constant>, defined in the <link
251	linkend="videodev">videodev.h</link> header file. These identifiers
252	represent <link linkend="v4l2-fourcc">four character (FourCC) codes</link>
253	which are also listed below, however they are not the same as those
254	used in the Windows world.</para>
255	
256	    <para>For some formats, data is stored in separate, discontiguous
257	memory buffers. Those formats are identified by a separate set of FourCC codes
258	and are referred to as "multi-planar formats". For example, a YUV422 frame is
259	normally stored in one memory buffer, but it can also be placed in two or three
260	separate buffers, with Y component in one buffer and CbCr components in another
261	in the 2-planar version or with each component in its own buffer in the
262	3-planar case. Those sub-buffers are referred to as "planes".</para>
263	  </section>
264	
265	  <section id="colorspaces">
266	    <title>Colorspaces</title>
267	
268	    <para>[intro]</para>
269	
270	    <!-- See proposal by Billy Biggs, video4linux-list@redhat.com
271	on 11 Oct 2002, subject: "Re: [V4L] Re: v4l2 api", and
272	http://vektor.theorem.ca/graphics/ycbcr/ and
273	http://www.poynton.com/notes/colour_and_gamma/ColorFAQ.html -->
274	
275	    <para>
276	      <variablelist>
277		<varlistentry>
278		  <term>Gamma Correction</term>
279		  <listitem>
280		    <para>[to do]</para>
281		    <para>E'<subscript>R</subscript> = f(R)</para>
282		    <para>E'<subscript>G</subscript> = f(G)</para>
283		    <para>E'<subscript>B</subscript> = f(B)</para>
284		  </listitem>
285		</varlistentry>
286		<varlistentry>
287		  <term>Construction of luminance and color-difference
288	signals</term>
289		  <listitem>
290		    <para>[to do]</para>
291		    <para>E'<subscript>Y</subscript> =
292	Coeff<subscript>R</subscript> E'<subscript>R</subscript>
293	+ Coeff<subscript>G</subscript> E'<subscript>G</subscript>
294	+ Coeff<subscript>B</subscript> E'<subscript>B</subscript></para>
295		    <para>(E'<subscript>R</subscript> - E'<subscript>Y</subscript>) = E'<subscript>R</subscript>
296	- Coeff<subscript>R</subscript> E'<subscript>R</subscript>
297	- Coeff<subscript>G</subscript> E'<subscript>G</subscript>
298	- Coeff<subscript>B</subscript> E'<subscript>B</subscript></para>
299		    <para>(E'<subscript>B</subscript> - E'<subscript>Y</subscript>) = E'<subscript>B</subscript>
300	- Coeff<subscript>R</subscript> E'<subscript>R</subscript>
301	- Coeff<subscript>G</subscript> E'<subscript>G</subscript>
302	- Coeff<subscript>B</subscript> E'<subscript>B</subscript></para>
303		  </listitem>
304		</varlistentry>
305		<varlistentry>
306		  <term>Re-normalized color-difference signals</term>
307		  <listitem>
308		    <para>The color-difference signals are scaled back to unity
309	range [-0.5;+0.5]:</para>
310		    <para>K<subscript>B</subscript> = 0.5 / (1 - Coeff<subscript>B</subscript>)</para>
311		    <para>K<subscript>R</subscript> = 0.5 / (1 - Coeff<subscript>R</subscript>)</para>
312		    <para>P<subscript>B</subscript> =
313	K<subscript>B</subscript> (E'<subscript>B</subscript> - E'<subscript>Y</subscript>) =
314	  0.5 (Coeff<subscript>R</subscript> / Coeff<subscript>B</subscript>) E'<subscript>R</subscript>
315	+ 0.5 (Coeff<subscript>G</subscript> / Coeff<subscript>B</subscript>) E'<subscript>G</subscript>
316	+ 0.5 E'<subscript>B</subscript></para>
317		    <para>P<subscript>R</subscript> =
318	K<subscript>R</subscript> (E'<subscript>R</subscript> - E'<subscript>Y</subscript>) =
319	  0.5 E'<subscript>R</subscript>
320	+ 0.5 (Coeff<subscript>G</subscript> / Coeff<subscript>R</subscript>) E'<subscript>G</subscript>
321	+ 0.5 (Coeff<subscript>B</subscript> / Coeff<subscript>R</subscript>) E'<subscript>B</subscript></para>
322		  </listitem>
323		</varlistentry>
324		<varlistentry>
325		  <term>Quantization</term>
326		  <listitem>
327		    <para>[to do]</para>
328		    <para>Y' = (Lum. Levels - 1) &middot; E'<subscript>Y</subscript> + Lum. Offset</para>
329		    <para>C<subscript>B</subscript> = (Chrom. Levels - 1)
330	&middot; P<subscript>B</subscript> + Chrom. Offset</para>
331		    <para>C<subscript>R</subscript> = (Chrom. Levels - 1)
332	&middot; P<subscript>R</subscript> + Chrom. Offset</para>
333		    <para>Rounding to the nearest integer and clamping to the range
334	[0;255] finally yields the digital color components Y'CbCr
335	stored in YUV images.</para>
336		  </listitem>
337		</varlistentry>
338	      </variablelist>
339	    </para>
340	
341	    <example>
342	      <title>ITU-R Rec. BT.601 color conversion</title>
343	
344	      <para>Forward Transformation</para>
345	
346	      <programlisting>
347	int ER, EG, EB;         /* gamma corrected RGB input [0;255] */
348	int Y1, Cb, Cr;         /* output [0;255] */
349	
350	double r, g, b;         /* temporaries */
351	double y1, pb, pr;
352	
353	int
354	clamp (double x)
355	{
356		int r = x;      /* round to nearest */
357	
358		if (r &lt; 0)         return 0;
359		else if (r &gt; 255)  return 255;
360		else               return r;
361	}
362	
363	r = ER / 255.0;
364	g = EG / 255.0;
365	b = EB / 255.0;
366	
367	y1  =  0.299  * r + 0.587 * g + 0.114  * b;
368	pb  = -0.169  * r - 0.331 * g + 0.5    * b;
369	pr  =  0.5    * r - 0.419 * g - 0.081  * b;
370	
371	Y1 = clamp (219 * y1 + 16);
372	Cb = clamp (224 * pb + 128);
373	Cr = clamp (224 * pr + 128);
374	
375	/* or shorter */
376	
377	y1 = 0.299 * ER + 0.587 * EG + 0.114 * EB;
378	
379	Y1 = clamp ( (219 / 255.0)                    *       y1  + 16);
380	Cb = clamp (((224 / 255.0) / (2 - 2 * 0.114)) * (EB - y1) + 128);
381	Cr = clamp (((224 / 255.0) / (2 - 2 * 0.299)) * (ER - y1) + 128);
382	      </programlisting>
383	
384	      <para>Inverse Transformation</para>
385	
386	      <programlisting>
387	int Y1, Cb, Cr;         /* gamma pre-corrected input [0;255] */
388	int ER, EG, EB;         /* output [0;255] */
389	
390	double r, g, b;         /* temporaries */
391	double y1, pb, pr;
392	
393	int
394	clamp (double x)
395	{
396		int r = x;      /* round to nearest */
397	
398		if (r &lt; 0)         return 0;
399		else if (r &gt; 255)  return 255;
400		else               return r;
401	}
402	
403	y1 = (Y1 - 16) / 219.0;
404	pb = (Cb - 128) / 224.0;
405	pr = (Cr - 128) / 224.0;
406	
407	r = 1.0 * y1 + 0     * pb + 1.402 * pr;
408	g = 1.0 * y1 - 0.344 * pb - 0.714 * pr;
409	b = 1.0 * y1 + 1.772 * pb + 0     * pr;
410	
411	ER = clamp (r * 255); /* [ok? one should prob. limit y1,pb,pr] */
412	EG = clamp (g * 255);
413	EB = clamp (b * 255);
414	      </programlisting>
415	    </example>
416	
417	    <table pgwide="1" id="v4l2-colorspace" orient="land">
418	      <title>enum v4l2_colorspace</title>
419	      <tgroup cols="11" align="center">
420		<colspec align="left" />
421		<colspec align="center" />
422		<colspec align="left" />
423		<colspec colname="cr" />
424		<colspec colname="cg" />
425		<colspec colname="cb" />
426		<colspec colname="wp" />
427		<colspec colname="gc" />
428		<colspec colname="lum" />
429		<colspec colname="qy" />
430		<colspec colname="qc" />
431		<spanspec namest="cr" nameend="cb" spanname="chrom" />
432		<spanspec namest="qy" nameend="qc" spanname="quant" />
433		<spanspec namest="lum" nameend="qc" spanname="spam" />
434		<thead>
435		  <row>
436		    <entry morerows="1">Identifier</entry>
437		    <entry morerows="1">Value</entry>
438		    <entry morerows="1">Description</entry>
439		    <entry spanname="chrom">Chromaticities<footnote>
440			<para>The coordinates of the color primaries are
441	given in the CIE system (1931)</para>
442		      </footnote></entry>
443		    <entry morerows="1">White Point</entry>
444		    <entry morerows="1">Gamma Correction</entry>
445		    <entry morerows="1">Luminance E'<subscript>Y</subscript></entry>
446		    <entry spanname="quant">Quantization</entry>
447		  </row>
448		  <row>
449		    <entry>Red</entry>
450		    <entry>Green</entry>
451		    <entry>Blue</entry>
452		    <entry>Y'</entry>
453		    <entry>Cb, Cr</entry>
454		  </row>
455		</thead>
456		<tbody valign="top">
457		  <row>
458		    <entry><constant>V4L2_COLORSPACE_SMPTE170M</constant></entry>
459		    <entry>1</entry>
460		    <entry>NTSC/PAL according to <xref linkend="smpte170m" />,
461	<xref linkend="itu601" /></entry>
462		    <entry>x&nbsp;=&nbsp;0.630, y&nbsp;=&nbsp;0.340</entry>
463		    <entry>x&nbsp;=&nbsp;0.310, y&nbsp;=&nbsp;0.595</entry>
464		    <entry>x&nbsp;=&nbsp;0.155, y&nbsp;=&nbsp;0.070</entry>
465		    <entry>x&nbsp;=&nbsp;0.3127, y&nbsp;=&nbsp;0.3290,
466		    Illuminant D<subscript>65</subscript></entry>
467		    <entry>E' = 4.5&nbsp;I&nbsp;for&nbsp;I&nbsp;&le;0.018,
468	1.099&nbsp;I<superscript>0.45</superscript>&nbsp;-&nbsp;0.099&nbsp;for&nbsp;0.018&nbsp;&lt;&nbsp;I</entry>
469		    <entry>0.299&nbsp;E'<subscript>R</subscript>
470	+&nbsp;0.587&nbsp;E'<subscript>G</subscript>
471	+&nbsp;0.114&nbsp;E'<subscript>B</subscript></entry>
472		    <entry>219&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
473		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
474		  </row>
475		  <row>
476		    <entry><constant>V4L2_COLORSPACE_SMPTE240M</constant></entry>
477		    <entry>2</entry>
478		    <entry>1125-Line (US) HDTV, see <xref
479	linkend="smpte240m" /></entry>
480		    <entry>x&nbsp;=&nbsp;0.630, y&nbsp;=&nbsp;0.340</entry>
481		    <entry>x&nbsp;=&nbsp;0.310, y&nbsp;=&nbsp;0.595</entry>
482		    <entry>x&nbsp;=&nbsp;0.155, y&nbsp;=&nbsp;0.070</entry>
483		    <entry>x&nbsp;=&nbsp;0.3127, y&nbsp;=&nbsp;0.3290,
484		    Illuminant D<subscript>65</subscript></entry>
485		    <entry>E' = 4&nbsp;I&nbsp;for&nbsp;I&nbsp;&le;0.0228,
486	1.1115&nbsp;I<superscript>0.45</superscript>&nbsp;-&nbsp;0.1115&nbsp;for&nbsp;0.0228&nbsp;&lt;&nbsp;I</entry>
487		    <entry>0.212&nbsp;E'<subscript>R</subscript>
488	+&nbsp;0.701&nbsp;E'<subscript>G</subscript>
489	+&nbsp;0.087&nbsp;E'<subscript>B</subscript></entry>
490		    <entry>219&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
491		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
492		  </row>
493		  <row>
494		    <entry><constant>V4L2_COLORSPACE_REC709</constant></entry>
495		    <entry>3</entry>
496		    <entry>HDTV and modern devices, see <xref
497	linkend="itu709" /></entry>
498		    <entry>x&nbsp;=&nbsp;0.640, y&nbsp;=&nbsp;0.330</entry>
499		    <entry>x&nbsp;=&nbsp;0.300, y&nbsp;=&nbsp;0.600</entry>
500		    <entry>x&nbsp;=&nbsp;0.150, y&nbsp;=&nbsp;0.060</entry>
501		    <entry>x&nbsp;=&nbsp;0.3127, y&nbsp;=&nbsp;0.3290,
502		    Illuminant D<subscript>65</subscript></entry>
503		    <entry>E' = 4.5&nbsp;I&nbsp;for&nbsp;I&nbsp;&le;0.018,
504	1.099&nbsp;I<superscript>0.45</superscript>&nbsp;-&nbsp;0.099&nbsp;for&nbsp;0.018&nbsp;&lt;&nbsp;I</entry>
505		    <entry>0.2125&nbsp;E'<subscript>R</subscript>
506	+&nbsp;0.7154&nbsp;E'<subscript>G</subscript>
507	+&nbsp;0.0721&nbsp;E'<subscript>B</subscript></entry>
508		    <entry>219&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
509		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
510		  </row>
511		  <row>
512		    <entry><constant>V4L2_COLORSPACE_BT878</constant></entry>
513		    <entry>4</entry>
514		    <entry>Broken Bt878 extents<footnote>
515			<para>The ubiquitous Bt878 video capture chip
516	quantizes E'<subscript>Y</subscript> to 238 levels, yielding a range
517	of Y' = 16 &hellip; 253, unlike Rec. 601 Y' = 16 &hellip;
518	235. This is not a typo in the Bt878 documentation, it has been
519	implemented in silicon. The chroma extents are unclear.</para>
520		      </footnote>, <xref linkend="itu601" /></entry>
521		    <entry>?</entry>
522		    <entry>?</entry>
523		    <entry>?</entry>
524		    <entry>?</entry>
525		    <entry>?</entry>
526		    <entry>0.299&nbsp;E'<subscript>R</subscript>
527	+&nbsp;0.587&nbsp;E'<subscript>G</subscript>
528	+&nbsp;0.114&nbsp;E'<subscript>B</subscript></entry>
529		    <entry><emphasis>237</emphasis>&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
530		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128 (probably)</entry>
531		  </row>
532		  <row>
533		    <entry><constant>V4L2_COLORSPACE_470_SYSTEM_M</constant></entry>
534		    <entry>5</entry>
535		    <entry>M/NTSC<footnote>
536			<para>No identifier exists for M/PAL which uses
537	the chromaticities of M/NTSC, the remaining parameters are equal to B and
538	G/PAL.</para>
539		      </footnote> according to <xref linkend="itu470" />, <xref
540			linkend="itu601" /></entry>
541		    <entry>x&nbsp;=&nbsp;0.67, y&nbsp;=&nbsp;0.33</entry>
542		    <entry>x&nbsp;=&nbsp;0.21, y&nbsp;=&nbsp;0.71</entry>
543		    <entry>x&nbsp;=&nbsp;0.14, y&nbsp;=&nbsp;0.08</entry>
544		    <entry>x&nbsp;=&nbsp;0.310, y&nbsp;=&nbsp;0.316, Illuminant C</entry>
545		    <entry>?</entry>
546		    <entry>0.299&nbsp;E'<subscript>R</subscript>
547	+&nbsp;0.587&nbsp;E'<subscript>G</subscript>
548	+&nbsp;0.114&nbsp;E'<subscript>B</subscript></entry>
549		    <entry>219&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
550		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
551		  </row>
552		  <row>
553		    <entry><constant>V4L2_COLORSPACE_470_SYSTEM_BG</constant></entry>
554		    <entry>6</entry>
555		    <entry>625-line PAL and SECAM systems according to <xref
556	linkend="itu470" />, <xref linkend="itu601" /></entry>
557		    <entry>x&nbsp;=&nbsp;0.64, y&nbsp;=&nbsp;0.33</entry>
558		    <entry>x&nbsp;=&nbsp;0.29, y&nbsp;=&nbsp;0.60</entry>
559		    <entry>x&nbsp;=&nbsp;0.15, y&nbsp;=&nbsp;0.06</entry>
560		    <entry>x&nbsp;=&nbsp;0.313, y&nbsp;=&nbsp;0.329,
561	Illuminant D<subscript>65</subscript></entry>
562		    <entry>?</entry>
563		    <entry>0.299&nbsp;E'<subscript>R</subscript>
564	+&nbsp;0.587&nbsp;E'<subscript>G</subscript>
565	+&nbsp;0.114&nbsp;E'<subscript>B</subscript></entry>
566		    <entry>219&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16</entry>
567		    <entry>224&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
568		  </row>
569		  <row>
570		    <entry><constant>V4L2_COLORSPACE_JPEG</constant></entry>
571		    <entry>7</entry>
572		    <entry>JPEG Y'CbCr, see <xref linkend="jfif" />, <xref linkend="itu601" /></entry>
573		    <entry>?</entry>
574		    <entry>?</entry>
575		    <entry>?</entry>
576		    <entry>?</entry>
577		    <entry>?</entry>
578		    <entry>0.299&nbsp;E'<subscript>R</subscript>
579	+&nbsp;0.587&nbsp;E'<subscript>G</subscript>
580	+&nbsp;0.114&nbsp;E'<subscript>B</subscript></entry>
581		    <entry>256&nbsp;E'<subscript>Y</subscript>&nbsp;+&nbsp;16<footnote>
582			<para>Note JFIF quantizes
583	Y'P<subscript>B</subscript>P<subscript>R</subscript> in range [0;+1] and
584	[-0.5;+0.5] to <emphasis>257</emphasis> levels, however Y'CbCr signals
585	are still clamped to [0;255].</para>
586		      </footnote></entry>
587		    <entry>256&nbsp;P<subscript>B,R</subscript>&nbsp;+&nbsp;128</entry>
588		  </row>
589		  <row>
590		    <entry><constant>V4L2_COLORSPACE_SRGB</constant></entry>
591		    <entry>8</entry>
592		    <entry>[?]</entry>
593		    <entry>x&nbsp;=&nbsp;0.640, y&nbsp;=&nbsp;0.330</entry>
594		    <entry>x&nbsp;=&nbsp;0.300, y&nbsp;=&nbsp;0.600</entry>
595		    <entry>x&nbsp;=&nbsp;0.150, y&nbsp;=&nbsp;0.060</entry>
596		    <entry>x&nbsp;=&nbsp;0.3127, y&nbsp;=&nbsp;0.3290,
597		    Illuminant D<subscript>65</subscript></entry>
598		    <entry>E' = 4.5&nbsp;I&nbsp;for&nbsp;I&nbsp;&le;0.018,
599	1.099&nbsp;I<superscript>0.45</superscript>&nbsp;-&nbsp;0.099&nbsp;for&nbsp;0.018&nbsp;&lt;&nbsp;I</entry>
600		    <entry spanname="spam">n/a</entry>
601		  </row>
602		</tbody>
603	      </tgroup>
604	    </table>
605	  </section>
606	
607	  <section id="pixfmt-indexed">
608	    <title>Indexed Format</title>
609	
610	    <para>In this format each pixel is represented by an 8 bit index
611	into a 256 entry ARGB palette. It is intended for <link
612	linkend="osd">Video Output Overlays</link> only. There are no ioctls to
613	access the palette, this must be done with ioctls of the Linux framebuffer API.</para>
614	
615	    <table pgwide="0" frame="none">
616	      <title>Indexed Image Format</title>
617	      <tgroup cols="37" align="center">
618		<colspec colname="id" align="left" />
619		<colspec colname="fourcc" />
620		<colspec colname="bit" />
621	
622		<colspec colnum="4" colname="b07" align="center" />
623		<colspec colnum="5" colname="b06" align="center" />
624		<colspec colnum="6" colname="b05" align="center" />
625		<colspec colnum="7" colname="b04" align="center" />
626		<colspec colnum="8" colname="b03" align="center" />
627		<colspec colnum="9" colname="b02" align="center" />
628		<colspec colnum="10" colname="b01" align="center" />
629		<colspec colnum="11" colname="b00" align="center" />
630	
631		<spanspec namest="b07" nameend="b00" spanname="b0" />
632		<spanspec namest="b17" nameend="b10" spanname="b1" />
633		<spanspec namest="b27" nameend="b20" spanname="b2" />
634		<spanspec namest="b37" nameend="b30" spanname="b3" />
635		<thead>
636		  <row>
637		    <entry>Identifier</entry>
638		    <entry>Code</entry>
639		    <entry>&nbsp;</entry>
640		    <entry spanname="b0">Byte&nbsp;0</entry>
641		  </row>
642		  <row>
643		    <entry>&nbsp;</entry>
644		    <entry>&nbsp;</entry>
645		    <entry>Bit</entry>
646		    <entry>7</entry>
647		    <entry>6</entry>
648		    <entry>5</entry>
649		    <entry>4</entry>
650		    <entry>3</entry>
651		    <entry>2</entry>
652		    <entry>1</entry>
653		    <entry>0</entry>
654		  </row>
655		</thead>
656		<tbody valign="top">
657		  <row id="V4L2-PIX-FMT-PAL8">
658		    <entry><constant>V4L2_PIX_FMT_PAL8</constant></entry>
659		    <entry>'PAL8'</entry>
660		    <entry></entry>
661		    <entry>i<subscript>7</subscript></entry>
662		    <entry>i<subscript>6</subscript></entry>
663		    <entry>i<subscript>5</subscript></entry>
664		    <entry>i<subscript>4</subscript></entry>
665		    <entry>i<subscript>3</subscript></entry>
666		    <entry>i<subscript>2</subscript></entry>
667		    <entry>i<subscript>1</subscript></entry>
668		    <entry>i<subscript>0</subscript></entry>
669		  </row>
670		</tbody>
671	      </tgroup>
672	    </table>
673	  </section>
674	
675	  <section id="pixfmt-rgb">
676	    <title>RGB Formats</title>
677	
678	    &sub-packed-rgb;
679	    &sub-sbggr8;
680	    &sub-sgbrg8;
681	    &sub-sgrbg8;
682	    &sub-srggb8;
683	    &sub-sbggr16;
684	    &sub-srggb10;
685	    &sub-srggb10alaw8;
686	    &sub-srggb10dpcm8;
687	    &sub-srggb12;
688	  </section>
689	
690	  <section id="yuv-formats">
691	    <title>YUV Formats</title>
692	
693	    <para>YUV is the format native to TV broadcast and composite video
694	signals. It separates the brightness information (Y) from the color
695	information (U and V or Cb and Cr). The color information consists of
696	red and blue <emphasis>color difference</emphasis> signals, this way
697	the green component can be reconstructed by subtracting from the
698	brightness component. See <xref linkend="colorspaces" /> for conversion
699	examples. YUV was chosen because early television would only transmit
700	brightness information. To add color in a way compatible with existing
701	receivers a new signal carrier was added to transmit the color
702	difference signals. Secondary in the YUV format the U and V components
703	usually have lower resolution than the Y component. This is an analog
704	video compression technique taking advantage of a property of the
705	human visual system, being more sensitive to brightness
706	information.</para>
707	
708	    &sub-packed-yuv;
709	    &sub-grey;
710	    &sub-y10;
711	    &sub-y12;
712	    &sub-y10b;
713	    &sub-y16;
714	    &sub-uv8;
715	    &sub-yuyv;
716	    &sub-uyvy;
717	    &sub-yvyu;
718	    &sub-vyuy;
719	    &sub-y41p;
720	    &sub-yuv420;
721	    &sub-yuv420m;
722	    &sub-yvu420m;
723	    &sub-yuv410;
724	    &sub-yuv422p;
725	    &sub-yuv411p;
726	    &sub-nv12;
727	    &sub-nv12m;
728	    &sub-nv12mt;
729	    &sub-nv16;
730	    &sub-nv16m;
731	    &sub-nv24;
732	    &sub-m420;
733	  </section>
734	
735	  <section>
736	    <title>Compressed Formats</title>
737	
738	    <table pgwide="1" frame="none" id="compressed-formats">
739	      <title>Compressed Image Formats</title>
740	      <tgroup cols="3" align="left">
741		&cs-def;
742		<thead>
743		  <row>
744		    <entry>Identifier</entry>
745		    <entry>Code</entry>
746		    <entry>Details</entry>
747		  </row>
748		</thead>
749		<tbody valign="top">
750		 <row id="V4L2-PIX-FMT-JPEG">
751		    <entry><constant>V4L2_PIX_FMT_JPEG</constant></entry>
752		    <entry>'JPEG'</entry>
753		    <entry>TBD. See also &VIDIOC-G-JPEGCOMP;,
754		    &VIDIOC-S-JPEGCOMP;.</entry>
755		  </row>
756		  <row id="V4L2-PIX-FMT-MPEG">
757		    <entry><constant>V4L2_PIX_FMT_MPEG</constant></entry>
758		    <entry>'MPEG'</entry>
759		    <entry>MPEG multiplexed stream. The actual format is determined by
760	extended control <constant>V4L2_CID_MPEG_STREAM_TYPE</constant>, see
761	<xref linkend="mpeg-control-id" />.</entry>
762		  </row>
763		  <row id="V4L2-PIX-FMT-H264">
764			<entry><constant>V4L2_PIX_FMT_H264</constant></entry>
765			<entry>'H264'</entry>
766			<entry>H264 video elementary stream with start codes.</entry>
767		  </row>
768		  <row id="V4L2-PIX-FMT-H264-NO-SC">
769			<entry><constant>V4L2_PIX_FMT_H264_NO_SC</constant></entry>
770			<entry>'AVC1'</entry>
771			<entry>H264 video elementary stream without start codes.</entry>
772		  </row>
773		  <row id="V4L2-PIX-FMT-H264-MVC">
774			<entry><constant>V4L2_PIX_FMT_H264_MVC</constant></entry>
775			<entry>'M264'</entry>
776			<entry>H264 MVC video elementary stream.</entry>
777		  </row>
778		  <row id="V4L2-PIX-FMT-H263">
779			<entry><constant>V4L2_PIX_FMT_H263</constant></entry>
780			<entry>'H263'</entry>
781			<entry>H263 video elementary stream.</entry>
782		  </row>
783		  <row id="V4L2-PIX-FMT-MPEG1">
784			<entry><constant>V4L2_PIX_FMT_MPEG1</constant></entry>
785			<entry>'MPG1'</entry>
786			<entry>MPEG1 video elementary stream.</entry>
787		  </row>
788		  <row id="V4L2-PIX-FMT-MPEG2">
789			<entry><constant>V4L2_PIX_FMT_MPEG2</constant></entry>
790			<entry>'MPG2'</entry>
791			<entry>MPEG2 video elementary stream.</entry>
792		  </row>
793		  <row id="V4L2-PIX-FMT-MPEG4">
794			<entry><constant>V4L2_PIX_FMT_MPEG4</constant></entry>
795			<entry>'MPG4'</entry>
796			<entry>MPEG4 video elementary stream.</entry>
797		  </row>
798		  <row id="V4L2-PIX-FMT-XVID">
799			<entry><constant>V4L2_PIX_FMT_XVID</constant></entry>
800			<entry>'XVID'</entry>
801			<entry>Xvid video elementary stream.</entry>
802		  </row>
803		  <row id="V4L2-PIX-FMT-VC1-ANNEX-G">
804			<entry><constant>V4L2_PIX_FMT_VC1_ANNEX_G</constant></entry>
805			<entry>'VC1G'</entry>
806			<entry>VC1, SMPTE 421M Annex G compliant stream.</entry>
807		  </row>
808		  <row id="V4L2-PIX-FMT-VC1-ANNEX-L">
809			<entry><constant>V4L2_PIX_FMT_VC1_ANNEX_L</constant></entry>
810			<entry>'VC1L'</entry>
811			<entry>VC1, SMPTE 421M Annex L compliant stream.</entry>
812		  </row>
813		  <row id="V4L2-PIX-FMT-VP8">
814			<entry><constant>V4L2_PIX_FMT_VP8</constant></entry>
815			<entry>'VP80'</entry>
816			<entry>VP8 video elementary stream.</entry>
817		  </row>
818		</tbody>
819	      </tgroup>
820	    </table>
821	  </section>
822	
823	  <section id="sdr-formats">
824	    <title>SDR Formats</title>
825	
826	    <para>These formats are used for <link linkend="sdr">SDR Capture</link>
827	interface only.</para>
828	
829	    &sub-sdr-cu08;
830	    &sub-sdr-cu16le;
831	
832	  </section>
833	
834	  <section id="pixfmt-reserved">
835	    <title>Reserved Format Identifiers</title>
836	
837	    <para>These formats are not defined by this specification, they
838	are just listed for reference and to avoid naming conflicts. If you
839	want to register your own format, send an e-mail to the linux-media mailing
840	list &v4l-ml; for inclusion in the <filename>videodev2.h</filename>
841	file. If you want to share your format with other developers add a
842	link to your documentation and send a copy to the linux-media mailing list
843	for inclusion in this section. If you think your format should be listed
844	in a standard format section please make a proposal on the linux-media mailing
845	list.</para>
846	
847	    <table pgwide="1" frame="none" id="reserved-formats">
848	      <title>Reserved Image Formats</title>
849	      <tgroup cols="3" align="left">
850		&cs-def;
851		<thead>
852		  <row>
853		    <entry>Identifier</entry>
854		    <entry>Code</entry>
855		    <entry>Details</entry>
856		  </row>
857		</thead>
858		<tbody valign="top">
859		  <row id="V4L2-PIX-FMT-DV">
860		    <entry><constant>V4L2_PIX_FMT_DV</constant></entry>
861		    <entry>'dvsd'</entry>
862		    <entry>unknown</entry>
863		  </row>
864		  <row id="V4L2-PIX-FMT-ET61X251">
865		    <entry><constant>V4L2_PIX_FMT_ET61X251</constant></entry>
866		    <entry>'E625'</entry>
867		    <entry>Compressed format of the ET61X251 driver.</entry>
868		  </row>
869		  <row id="V4L2-PIX-FMT-HI240">
870		    <entry><constant>V4L2_PIX_FMT_HI240</constant></entry>
871		    <entry>'HI24'</entry>
872		    <entry><para>8 bit RGB format used by the BTTV driver.</para></entry>
873		  </row>
874		  <row id="V4L2-PIX-FMT-HM12">
875		    <entry><constant>V4L2_PIX_FMT_HM12</constant></entry>
876		    <entry>'HM12'</entry>
877		    <entry><para>YUV 4:2:0 format used by the
878	IVTV driver, <ulink url="http://www.ivtvdriver.org/">
879	http://www.ivtvdriver.org/</ulink></para><para>The format is documented in the
880	kernel sources in the file <filename>Documentation/video4linux/cx2341x/README.hm12</filename>
881	</para></entry>
882		  </row>
883		  <row id="V4L2-PIX-FMT-CPIA1">
884		    <entry><constant>V4L2_PIX_FMT_CPIA1</constant></entry>
885		    <entry>'CPIA'</entry>
886		    <entry>YUV format used by the gspca cpia1 driver.</entry>
887		  </row>
888		  <row id="V4L2-PIX-FMT-JPGL">
889		    <entry><constant>V4L2_PIX_FMT_JPGL</constant></entry>
890		    <entry>'JPGL'</entry>
891		    <entry>JPEG-Light format (Pegasus Lossless JPEG)
892				used in Divio webcams NW 80x.</entry>
893		  </row>
894		  <row id="V4L2-PIX-FMT-SPCA501">
895		    <entry><constant>V4L2_PIX_FMT_SPCA501</constant></entry>
896		    <entry>'S501'</entry>
897		    <entry>YUYV per line used by the gspca driver.</entry>
898		  </row>
899		  <row id="V4L2-PIX-FMT-SPCA505">
900		    <entry><constant>V4L2_PIX_FMT_SPCA505</constant></entry>
901		    <entry>'S505'</entry>
902		    <entry>YYUV per line used by the gspca driver.</entry>
903		  </row>
904		  <row id="V4L2-PIX-FMT-SPCA508">
905		    <entry><constant>V4L2_PIX_FMT_SPCA508</constant></entry>
906		    <entry>'S508'</entry>
907		    <entry>YUVY per line used by the gspca driver.</entry>
908		  </row>
909		  <row id="V4L2-PIX-FMT-SPCA561">
910		    <entry><constant>V4L2_PIX_FMT_SPCA561</constant></entry>
911		    <entry>'S561'</entry>
912		    <entry>Compressed GBRG Bayer format used by the gspca driver.</entry>
913		  </row>
914		  <row id="V4L2-PIX-FMT-PAC207">
915		    <entry><constant>V4L2_PIX_FMT_PAC207</constant></entry>
916		    <entry>'P207'</entry>
917		    <entry>Compressed BGGR Bayer format used by the gspca driver.</entry>
918		  </row>
919		  <row id="V4L2-PIX-FMT-MR97310A">
920		    <entry><constant>V4L2_PIX_FMT_MR97310A</constant></entry>
921		    <entry>'M310'</entry>
922		    <entry>Compressed BGGR Bayer format used by the gspca driver.</entry>
923		  </row>
924		  <row id="V4L2-PIX-FMT-JL2005BCD">
925		    <entry><constant>V4L2_PIX_FMT_JL2005BCD</constant></entry>
926		    <entry>'JL20'</entry>
927		    <entry>JPEG compressed RGGB Bayer format used by the gspca driver.</entry>
928		  </row>
929		  <row id="V4L2-PIX-FMT-OV511">
930		    <entry><constant>V4L2_PIX_FMT_OV511</constant></entry>
931		    <entry>'O511'</entry>
932		    <entry>OV511 JPEG format used by the gspca driver.</entry>
933		  </row>
934		  <row id="V4L2-PIX-FMT-OV518">
935		    <entry><constant>V4L2_PIX_FMT_OV518</constant></entry>
936		    <entry>'O518'</entry>
937		    <entry>OV518 JPEG format used by the gspca driver.</entry>
938		  </row>
939		  <row id="V4L2-PIX-FMT-PJPG">
940		    <entry><constant>V4L2_PIX_FMT_PJPG</constant></entry>
941		    <entry>'PJPG'</entry>
942		    <entry>Pixart 73xx JPEG format used by the gspca driver.</entry>
943		  </row>
944		  <row id="V4L2-PIX-FMT-SE401">
945		    <entry><constant>V4L2_PIX_FMT_SE401</constant></entry>
946		    <entry>'S401'</entry>
947		    <entry>Compressed RGB format used by the gspca se401 driver</entry>
948		  </row>
949		  <row id="V4L2-PIX-FMT-SQ905C">
950		    <entry><constant>V4L2_PIX_FMT_SQ905C</constant></entry>
951		    <entry>'905C'</entry>
952		    <entry>Compressed RGGB bayer format used by the gspca driver.</entry>
953		  </row>
954		  <row id="V4L2-PIX-FMT-MJPEG">
955		    <entry><constant>V4L2_PIX_FMT_MJPEG</constant></entry>
956		    <entry>'MJPG'</entry>
957		    <entry>Compressed format used by the Zoran driver</entry>
958		  </row>
959		  <row id="V4L2-PIX-FMT-PWC1">
960		    <entry><constant>V4L2_PIX_FMT_PWC1</constant></entry>
961		    <entry>'PWC1'</entry>
962		    <entry>Compressed format of the PWC driver.</entry>
963		  </row>
964		  <row id="V4L2-PIX-FMT-PWC2">
965		    <entry><constant>V4L2_PIX_FMT_PWC2</constant></entry>
966		    <entry>'PWC2'</entry>
967		    <entry>Compressed format of the PWC driver.</entry>
968		  </row>
969		  <row id="V4L2-PIX-FMT-SN9C10X">
970		    <entry><constant>V4L2_PIX_FMT_SN9C10X</constant></entry>
971		    <entry>'S910'</entry>
972		    <entry>Compressed format of the SN9C102 driver.</entry>
973		  </row>
974		  <row id="V4L2-PIX-FMT-SN9C20X-I420">
975		    <entry><constant>V4L2_PIX_FMT_SN9C20X_I420</constant></entry>
976		    <entry>'S920'</entry>
977		    <entry>YUV 4:2:0 format of the gspca sn9c20x driver.</entry>
978		  </row>
979		  <row id="V4L2-PIX-FMT-SN9C2028">
980		    <entry><constant>V4L2_PIX_FMT_SN9C2028</constant></entry>
981		    <entry>'SONX'</entry>
982		    <entry>Compressed GBRG bayer format of the gspca sn9c2028 driver.</entry>
983		  </row>
984		  <row id="V4L2-PIX-FMT-STV0680">
985		    <entry><constant>V4L2_PIX_FMT_STV0680</constant></entry>
986		    <entry>'S680'</entry>
987		    <entry>Bayer format of the gspca stv0680 driver.</entry>
988		  </row>
989		  <row id="V4L2-PIX-FMT-WNVA">
990		    <entry><constant>V4L2_PIX_FMT_WNVA</constant></entry>
991		    <entry>'WNVA'</entry>
992		    <entry><para>Used by the Winnov Videum driver, <ulink
993	url="http://www.thedirks.org/winnov/">
994	http://www.thedirks.org/winnov/</ulink></para></entry>
995		  </row>
996		  <row id="V4L2-PIX-FMT-TM6000">
997		    <entry><constant>V4L2_PIX_FMT_TM6000</constant></entry>
998		    <entry>'TM60'</entry>
999		    <entry><para>Used by Trident tm6000</para></entry>
1000		  </row>
1001		  <row id="V4L2-PIX-FMT-CIT-YYVYUY">
1002		    <entry><constant>V4L2_PIX_FMT_CIT_YYVYUY</constant></entry>
1003		    <entry>'CITV'</entry>
1004		    <entry><para>Used by xirlink CIT, found at IBM webcams.</para>
1005		           <para>Uses one line of Y then 1 line of VYUY</para>
1006		    </entry>
1007		  </row>
1008		  <row id="V4L2-PIX-FMT-KONICA420">
1009		    <entry><constant>V4L2_PIX_FMT_KONICA420</constant></entry>
1010		    <entry>'KONI'</entry>
1011		    <entry><para>Used by Konica webcams.</para>
1012		           <para>YUV420 planar in blocks of 256 pixels.</para>
1013		    </entry>
1014		  </row>
1015		  <row id="V4L2-PIX-FMT-YYUV">
1016		    <entry><constant>V4L2_PIX_FMT_YYUV</constant></entry>
1017		    <entry>'YYUV'</entry>
1018		    <entry>unknown</entry>
1019		  </row>
1020		  <row id="V4L2-PIX-FMT-Y4">
1021		    <entry><constant>V4L2_PIX_FMT_Y4</constant></entry>
1022		    <entry>'Y04 '</entry>
1023		    <entry>Old 4-bit greyscale format. Only the most significant 4 bits of each byte are used,
1024	the other bits are set to 0.</entry>
1025		  </row>
1026		  <row id="V4L2-PIX-FMT-Y6">
1027		    <entry><constant>V4L2_PIX_FMT_Y6</constant></entry>
1028		    <entry>'Y06 '</entry>
1029		    <entry>Old 6-bit greyscale format. Only the most significant 6 bits of each byte are used,
1030	the other bits are set to 0.</entry>
1031		  </row>
1032		  <row id="V4L2-PIX-FMT-S5C-UYVY-JPG">
1033		    <entry><constant>V4L2_PIX_FMT_S5C_UYVY_JPG</constant></entry>
1034		    <entry>'S5CI'</entry>
1035		    <entry>Two-planar format used by Samsung S5C73MX cameras. The
1036	first plane contains interleaved JPEG and UYVY image data, followed by meta data
1037	in form of an array of offsets to the UYVY data blocks. The actual pointer array
1038	follows immediately the interleaved JPEG/UYVY data, the number of entries in
1039	this array equals the height of the UYVY image. Each entry is a 4-byte unsigned
1040	integer in big endian order and it's an offset to a single pixel line of the
1041	UYVY image. The first plane can start either with JPEG or UYVY data chunk. The
1042	size of a single UYVY block equals the UYVY image's width multiplied by 2. The
1043	size of a JPEG chunk depends on the image and can vary with each line.
1044	<para>The second plane, at an offset of 4084 bytes, contains a 4-byte offset to
1045	the pointer array in the first plane. This offset is followed by a 4-byte value
1046	indicating size of the pointer array. All numbers in the second plane are also
1047	in big endian order. Remaining data in the second plane is undefined. The
1048	information in the second plane allows to easily find location of the pointer
1049	array, which can be different for each frame. The size of the pointer array is
1050	constant for given UYVY image height.</para>
1051	<para>In order to extract UYVY and JPEG frames an application can initially set
1052	a data pointer to the start of first plane and then add an offset from the first
1053	entry of the pointers table. Such a pointer indicates start of an UYVY image
1054	pixel line. Whole UYVY line can be copied to a separate buffer. These steps
1055	should be repeated for each line, i.e. the number of entries in the pointer
1056	array. Anything what's in between the UYVY lines is JPEG data and should be
1057	concatenated to form the JPEG stream. </para>
1058	</entry>
1059		  </row>
1060		</tbody>
1061	      </tgroup>
1062	    </table>
1063	  </section>
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