videodev_mjpeg.h
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- /*****************************************************************************
- * Copyright (C) lavrec (see http://mjpeg.sourceforge.net)
- * ( XXX This file was get from the driver-zoran package and it is under GPL)
- *
- * $Id: videodev_mjpeg.h 6961 2004-03-05 17:34:23Z sam $
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
- *****************************************************************************/
- /* These are the MJPEG API extensions for the Video4Linux API,
- first introduced by the Iomega Buz driver by Rainer Johanni
- <rainer@johanni.de>
- */
- /* This is identical with the mgavideo internal params struct,
- please tell me if you change this struct here ! <gz@lysator.liu.se) */
- struct mjpeg_params
- {
- /* The following parameters can only be queried */
- int major_version; /* Major version number of driver */
- int minor_version; /* Minor version number of driver */
- /* Main control parameters */
- int input; /* Input channel: 0 = Composite, 1 = S-VHS */
- int norm; /* Norm: VIDEO_MODE_PAL or VIDEO_MODE_NTSC */
- int decimation; /* decimation of captured video,
- enlargement of video played back.
- Valid values are 1, 2, 4 or 0.
- 0 is a special value where the user
- has full control over video scaling */
- /* The following parameters only have to be set if decimation==0,
- for other values of decimation they provide the data how the image is captured */
- int HorDcm; /* Horizontal decimation: 1, 2 or 4 */
- int VerDcm; /* Vertical decimation: 1 or 2 */
- int TmpDcm; /* Temporal decimation: 1 or 2,
- if TmpDcm==2 in capture every second frame is dropped,
- in playback every frame is played twice */
- int field_per_buff; /* Number of fields per buffer: 1 or 2 */
- int img_x; /* start of image in x direction */
- int img_y; /* start of image in y direction */
- int img_width; /* image width BEFORE decimation,
- must be a multiple of HorDcm*16 */
- int img_height; /* image height BEFORE decimation,
- must be a multiple of VerDcm*8 */
- /* --- End of parameters for decimation==0 only --- */
- /* JPEG control parameters */
- int quality; /* Measure for quality of compressed images.
- Scales linearly with the size of the compressed images.
- Must be beetween 0 and 100, 100 is a compression
- ratio of 1:4 */
- int odd_even; /* Which field should come first ???
- This is more aptly named "top_first",
- i.e. (odd_even==1) --> top-field-first */
- int APPn; /* Number of APP segment to be written, must be 0..15 */
- int APP_len; /* Length of data in JPEG APPn segment */
- char APP_data[60]; /* Data in the JPEG APPn segment. */
- int COM_len; /* Length of data in JPEG COM segment */
- char COM_data[60]; /* Data in JPEG COM segment */
- unsigned long jpeg_markers; /* Which markers should go into the JPEG output.
- Unless you exactly know what you do, leave them untouched.
- Inluding less markers will make the resulting code
- smaller, but there will be fewer aplications
- which can read it.
- The presence of the APP and COM marker is
- influenced by APP0_len and COM_len ONLY! */
- #define JPEG_MARKER_DHT (1<<3) /* Define Huffman Tables */
- #define JPEG_MARKER_DQT (1<<4) /* Define Quantization Tables */
- #define JPEG_MARKER_DRI (1<<5) /* Define Restart Interval */
- #define JPEG_MARKER_COM (1<<6) /* Comment segment */
- #define JPEG_MARKER_APP (1<<7) /* App segment, driver will allways use APP0 */
- int VFIFO_FB; /* Flag for enabling Video Fifo Feedback.
- If this flag is turned on and JPEG decompressing
- is going to the screen, the decompress process
- is stopped every time the Video Fifo is full.
- This enables a smooth decompress to the screen
- but the video output signal will get scrambled */
- /* Misc */
- char reserved[312]; /* Makes 512 bytes for this structure */
- };
- struct mjpeg_requestbuffers
- {
- unsigned long count; /* Number of buffers for MJPEG grabbing */
- unsigned long size; /* Size PER BUFFER in bytes */
- };
- struct mjpeg_sync
- {
- unsigned long frame; /* Frame (0 - n) for double buffer */
- unsigned long length; /* number of code bytes in buffer (capture only) */
- unsigned long seq; /* frame sequence number */
- struct timeval timestamp; /* timestamp */
- };
- struct mjpeg_status
- {
- int input; /* Input channel, has to be set prior to BUZIOC_G_STATUS */
- int signal; /* Returned: 1 if valid video signal detected */
- int norm; /* Returned: VIDEO_MODE_PAL or VIDEO_MODE_NTSC */
- int color; /* Returned: 1 if color signal detected */
- };
- /*
- Private IOCTL to set up for displaying MJPEG
- */
- #define MJPIOC_G_PARAMS _IOR ('v', BASE_VIDIOCPRIVATE+0, struct mjpeg_params)
- #define MJPIOC_S_PARAMS _IOWR('v', BASE_VIDIOCPRIVATE+1, struct mjpeg_params)
- #define MJPIOC_REQBUFS _IOWR('v', BASE_VIDIOCPRIVATE+2, struct mjpeg_requestbuffers)
- #define MJPIOC_QBUF_CAPT _IOW ('v', BASE_VIDIOCPRIVATE+3, int)
- #define MJPIOC_QBUF_PLAY _IOW ('v', BASE_VIDIOCPRIVATE+4, int)
- #define MJPIOC_SYNC _IOR ('v', BASE_VIDIOCPRIVATE+5, struct mjpeg_sync)
- #define MJPIOC_G_STATUS _IOWR('v', BASE_VIDIOCPRIVATE+6, struct mjpeg_status)
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