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[media] gspca - sn9c20x: Add the JPEG compression quality control

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The JPEG compression quality was hardcoded to 95%. This value was too big,
raising often buffer overflows.
This quality is now 80% by default and is settable.

Signed-off-by: Jean-François Moine <moinejf@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Jean-François Moine 2012-03-19 04:35:34 -03:00 committed by Mauro Carvalho Chehab
parent 92884f80b7
commit 4c632e4e51
1 changed files with 37 additions and 4 deletions
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41
drivers/media/video/gspca/sn9c20x.c
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@ -79,6 +79,7 @@ enum e_ctrl {
EXPOSURE,
GAIN,
AUTOGAIN,
QUALITY,
NCTRLS /* number of controls */
};
@ -88,6 +89,8 @@ struct sd {
struct gspca_ctrl ctrls[NCTRLS];
u8 fmt; /* (used for JPEG QTAB update */
#define MIN_AVG_LUM 80
#define MAX_AVG_LUM 130
atomic_t avg_lum;
@ -101,7 +104,6 @@ struct sd {
u8 vstart;
u8 jpeg_hdr[JPEG_HDR_SZ];
u8 quality;
u8 flags;
};
@ -162,6 +164,7 @@ static void set_redblue(struct gspca_dev *gspca_dev);
static void set_hvflip(struct gspca_dev *gspca_dev);
static void set_exposure(struct gspca_dev *gspca_dev);
static void set_gain(struct gspca_dev *gspca_dev);
static void set_quality(struct gspca_dev *gspca_dev);
static const struct ctrl sd_ctrls[NCTRLS] = {
[BRIGHTNESS] = {
@ -307,6 +310,21 @@ static const struct ctrl sd_ctrls[NCTRLS] = {
.default_value = 1,
},
},
[QUALITY] = {
{
.id = V4L2_CID_JPEG_COMPRESSION_QUALITY,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Compression Quality",
#define QUALITY_MIN 50
#define QUALITY_MAX 90
#define QUALITY_DEF 80
.minimum = QUALITY_MIN,
.maximum = QUALITY_MAX,
.step = 1,
.default_value = QUALITY_DEF,
},
.set_control = set_quality
},
};
static const struct v4l2_pix_format vga_mode[] = {
@ -1732,6 +1750,21 @@ static void set_gain(struct gspca_dev *gspca_dev)
i2c_w(gspca_dev, gain);
}
static void set_quality(struct gspca_dev *gspca_dev)
{
struct sd *sd = (struct sd *) gspca_dev;
jpeg_set_qual(sd->jpeg_hdr, sd->ctrls[QUALITY].val);
reg_w1(gspca_dev, 0x1061, 0x01); /* stop transfer */
reg_w1(gspca_dev, 0x10e0, sd->fmt | 0x20); /* write QTAB */
reg_w(gspca_dev, 0x1100, &sd->jpeg_hdr[JPEG_QT0_OFFSET], 64);
reg_w(gspca_dev, 0x1140, &sd->jpeg_hdr[JPEG_QT1_OFFSET], 64);
reg_w1(gspca_dev, 0x1061, 0x03); /* restart transfer */
reg_w1(gspca_dev, 0x10e0, sd->fmt);
sd->fmt ^= 0x0c; /* invert QTAB use + write */
reg_w1(gspca_dev, 0x10e0, sd->fmt);
}
#ifdef CONFIG_VIDEO_ADV_DEBUG
static int sd_dbg_g_register(struct gspca_dev *gspca_dev,
struct v4l2_dbg_register *reg)
@ -1846,7 +1879,6 @@ static int sd_config(struct gspca_dev *gspca_dev,
gspca_dev->cam.ctrls = sd->ctrls;
sd->quality = 95;
return 0;
}
@ -2058,14 +2090,15 @@ static int sd_start(struct gspca_dev *gspca_dev)
jpeg_define(sd->jpeg_hdr, height, width,
0x21);
jpeg_set_qual(sd->jpeg_hdr, sd->quality);
jpeg_set_qual(sd->jpeg_hdr, sd->ctrls[QUALITY].val);
if (mode & MODE_RAW)
fmt = 0x2d;
else if (mode & MODE_JPEG)
fmt = 0x2c;
fmt = 0x24;
else
fmt = 0x2f; /* YUV 420 */
sd->fmt = fmt;
switch (mode & SCALE_MASK) {
case SCALE_1280x1024: