1 files changed, 146 insertions, 0 deletions

diff --git a/drivers/media/video/pwc/pwc-uncompress.c b/drivers/media/video/pwc/pwc-uncompress.c
new file mode 100644
index 000000000000..ef4204eab6c4
--- /dev/null
+++ b/drivers/media/video/pwc/pwc-uncompress.c
@@ -0,0 +1,146 @@
+/* Linux driver for Philips webcam
+   Decompression frontend.
+   (C) 1999-2003 Nemosoft Unv.
+   (C) 2004      Luc Saillard (luc@saillard.org)
+
+   NOTE: this version of pwc is an unofficial (modified) release of pwc & pcwx
+   driver and thus may have bugs that are not present in the original version.
+   Please send bug reports and support requests to <luc@saillard.org>.
+   The decompression routines have been implemented by reverse-engineering the
+   Nemosoft binary pwcx module. Caveat emptor.
+
+   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  02111-1307  USA
+*/
+
+#include <asm/current.h>
+#include <asm/types.h>
+
+#include "pwc.h"
+#include "pwc-uncompress.h"
+
+int pwc_decompress(struct pwc_device *pdev)
+{
+        struct pwc_frame_buf *fbuf;
+        int n, line, col, stride;
+        void *yuv, *image;
+        u16 *src;
+        u16 *dsty, *dstu, *dstv;
+
+        if (pdev == NULL)
+                return -EFAULT;
+#if defined(__KERNEL__) && defined(PWC_MAGIC)
+        if (pdev->magic != PWC_MAGIC) {
+                Err("pwc_decompress(): magic failed.\n");
+                return -EFAULT;
+        }
+#endif
+
+        fbuf = pdev->read_frame;
+        if (fbuf == NULL)
+                return -EFAULT;
+        image = pdev->image_ptr[pdev->fill_image];
+        if (!image)
+                return -EFAULT;
+
+        yuv = fbuf->data + pdev->frame_header_size;  /* Skip header */
+
+        /* Raw format; that's easy... */
+        if (pdev->vpalette == VIDEO_PALETTE_RAW)
+        {
+                memcpy(image, yuv, pdev->frame_size);
+                return 0;
+        }
+
+        if (pdev->vbandlength == 0) {
+                /* Uncompressed mode. We copy the data into the output buffer,
+                   using the viewport size (which may be larger than the image
+                   size). Unfortunately we have to do a bit of byte stuffing
+                   to get the desired output format/size.
+                 */
+                        /*
+                         * We do some byte shuffling here to go from the
+                         * native format to YUV420P.
+                         */
+                        src = (u16 *)yuv;
+                        n = pdev->view.x * pdev->view.y;
+
+                        /* offset in Y plane */
+                        stride = pdev->view.x * pdev->offset.y + pdev->offset.x;
+                        dsty = (u16 *)(image + stride);
+
+                        /* offsets in U/V planes */
+                        stride = pdev->view.x * pdev->offset.y / 4 + pdev->offset.x / 2;
+                        dstu = (u16 *)(image + n +         stride);
+                        dstv = (u16 *)(image + n + n / 4 + stride);
+
+                        /* increment after each line */
+                        stride = (pdev->view.x - pdev->image.x) / 2; /* u16 is 2 bytes */
+
+                        for (line = 0; line < pdev->image.y; line++) {
+                                for (col = 0; col < pdev->image.x; col += 4) {
+                                        *dsty++ = *src++;
+                                        *dsty++ = *src++;
+                                        if (line & 1)
+                                                *dstv++ = *src++;
+                                        else
+                                                *dstu++ = *src++;
+                                }
+                                dsty += stride;
+                                if (line & 1)
+                                        dstv += (stride >> 1);
+                                else
+                                        dstu += (stride >> 1);
+                        }
+        }
+        else {
+                /* Compressed; the decompressor routines will write the data
+                   in planar format immediately.
+                 */
+                int flags;
+                
+                flags = PWCX_FLAG_PLANAR;
+                if (pdev->vsize == PSZ_VGA && pdev->vframes == 5 && pdev->vsnapshot)
+                 {
+                   printk(KERN_ERR "pwc: Mode Bayer is not supported for now\n");
+                   flags |= PWCX_FLAG_BAYER;
+                   return -ENXIO; /* No such device or address: missing decompressor */
+                 }
+
+#if 0
+                switch (pdev->type)
+                 {
+                  case 675:
+                  case 680:
+                  case 690:
+                  case 720:
+                  case 730:
+                  case 740:
+                  case 750:
+                    pwc_dec23_decompress(&pdev->image, &pdev->view,
+                                &pdev->offset, yuv, image, flags,
+                                pdev->decompress_data, pdev->vbandlength);
+                    break;
+                  case 645:
+                  case 646:
+                    /* TODO & FIXME */
+                    return -ENXIO; /* Missing decompressor */
+                    break;
+                 }
+#endif
+        }
+        return 0;
+}
+
+