[PATCH v3] media: v4l2-ctrls: add control for dpcm predictor
From: Lad, Prabhakar prabhakar@ti.com
add V4L2_CID_DPCM_PREDICTOR control of type menu, which
determines the dpcm predictor. The predictor can be either
simple or advanced.
Signed-off-by: Lad, Prabhakar prabhakar@ti.com
Signed-off-by: Manjunath Hadli manjunath.ha...@ti.com
Cc: Sakari Ailus sakari.ai...@iki.fi
Cc: Hans Verkuil hans.verk...@cisco.com
Cc: Laurent Pinchart laurent.pinch...@ideasonboard.com
Cc: Mauro Carvalho Chehab mche...@infradead.org
Cc: Sylwester Nawrocki s.nawro...@samsung.com
Cc: Hans de Goede hdego...@redhat.com
Cc: Kyungmin Park kyungmin.p...@samsung.com
Cc: Rob Landley r...@landley.net
Cc: HeungJun Kim riverful@samsung.com
---
This patches has one checkpatch warning for line over
80 characters altough it can be avoided I have kept it
for consistency.
Changes for v3:
1: Added better explanation for DPCM, pointed by Hans.
Changes for v2:
1: Added documentaion in controls.xml pointed by Sylwester.
2: Chnaged V4L2_DPCM_PREDICTOR_ADVANCE to V4L2_DPCM_PREDICTOR_ADVANCED
pointed by Sakari.
Documentation/DocBook/media/v4l/controls.xml | 48 +-
drivers/media/v4l2-core/v4l2-ctrls.c |9 +
include/linux/videodev2.h|5 +++
3 files changed, 61 insertions(+), 1 deletions(-)
diff --git a/Documentation/DocBook/media/v4l/controls.xml
b/Documentation/DocBook/media/v4l/controls.xml
index 93b9c68..f704218 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -4267,7 +4267,53 @@ interface and may change in the future./para
pixels / second.
/entry
/row
- rowentry/entry/row
+ row
+ entry
spanname=idconstantV4L2_CID_DPCM_PREDICTOR/constant/entry
+ entrymenu/entry
+ /row
+ row id=v4l2-dpcm-predictor
+ entry spanname=descr Differential pulse-code modulation (DPCM)
is a signal
+ encoder that uses the baseline of pulse-code modulation (PCM) but
adds some
+ functionalities based on the prediction of the samples of the
signal. The input
+ can be an analog signal or a digital signal.
+
+ paraIf the input is a continuous-time
+ analog signal, it needs to be sampled first so that a discrete-time
signal is
+ the input to the DPCM encoder./para
+
+ paraSimple: take the values of two
+ consecutive samples; if they are analog samples, quantize them;
calculate the
+ difference between the first one and the next; the output is the
difference, and
+ it can be further entropy coded./para
+
+ paraAdvanced: instead of taking a difference relative to a
previous input sample,
+ take the difference relative to the output of a local model of the
decoder process;
+ in this option, the difference can be quantized, which allows a
good way to
+ incorporate a controlled loss in the encoding./para
+
+ paraApplying one of these two processes, short-term redundancy
(positive correlation of
+ nearby values) of the signal is eliminated; compression ratios on
the order of 2 to 4
+ can be achieved if differences are subsequently entropy coded,
because the entropy of
+ the difference signal is much smaller than that of the original
discrete signal treated
+ as independent samples.For more information about DPCM see ulink
+
url=http://en.wikipedia.org/wiki/Differential_pulse-code_modulation;Wikipedia/ulink./para
+ /entry
+ /row
+ row
+ entrytbl spanname=descr cols=2
+ tbody valign=top
+ row
+entryconstantV4L2_DPCM_PREDICTOR_SIMPLE/constant/entry
+ entryPredictor type is simple/entry
+ /row
+ row
+
entryconstantV4L2_DPCM_PREDICTOR_ADVANCED/constant/entry
+ entryPredictor type is advanced/entry
+ /row
+ /tbody
+ /entrytbl
+ /row
+ rowentry/entry/row
/tbody
/tgroup
/table
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index b6a2ee7..2d7bc15 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -425,6 +425,11 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
Gray,
NULL,
};
+ static const char * const dpcm_predictor[] = {
+ Simple Predictor,
+ Advanced Predictor,
+ NULL,
+ };
switch (id) {
case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
@@ -502,6 +507,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
return mpeg4_profile;
case V4L2_CID_JPEG_CHROMA_SUBSAMPLING:
return jpeg_chroma_subsampling;
+ case V4L2_CID_DPCM_PREDICTOR:
+ return
Re: [PATCH v3] media: v4l2-ctrls: add control for dpcm predictor
On Mon September 3 2012 09:20:51 Prabhakar Lad wrote:
From: Lad, Prabhakar prabhakar@ti.com
add V4L2_CID_DPCM_PREDICTOR control of type menu, which
determines the dpcm predictor. The predictor can be either
simple or advanced.
Signed-off-by: Lad, Prabhakar prabhakar@ti.com
Signed-off-by: Manjunath Hadli manjunath.ha...@ti.com
Cc: Sakari Ailus sakari.ai...@iki.fi
Cc: Hans Verkuil hans.verk...@cisco.com
Cc: Laurent Pinchart laurent.pinch...@ideasonboard.com
Cc: Mauro Carvalho Chehab mche...@infradead.org
Cc: Sylwester Nawrocki s.nawro...@samsung.com
Cc: Hans de Goede hdego...@redhat.com
Cc: Kyungmin Park kyungmin.p...@samsung.com
Cc: Rob Landley r...@landley.net
Cc: HeungJun Kim riverful@samsung.com
---
This patches has one checkpatch warning for line over
80 characters altough it can be avoided I have kept it
for consistency.
Changes for v3:
1: Added better explanation for DPCM, pointed by Hans.
Much better!
Acked-by: Hans Verkuil hans.verk...@cisco.com
Regards,
Hans
Changes for v2:
1: Added documentaion in controls.xml pointed by Sylwester.
2: Chnaged V4L2_DPCM_PREDICTOR_ADVANCE to V4L2_DPCM_PREDICTOR_ADVANCED
pointed by Sakari.
Documentation/DocBook/media/v4l/controls.xml | 48
+-
drivers/media/v4l2-core/v4l2-ctrls.c |9 +
include/linux/videodev2.h|5 +++
3 files changed, 61 insertions(+), 1 deletions(-)
diff --git a/Documentation/DocBook/media/v4l/controls.xml
b/Documentation/DocBook/media/v4l/controls.xml
index 93b9c68..f704218 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -4267,7 +4267,53 @@ interface and may change in the future./para
pixels / second.
/entry
/row
- rowentry/entry/row
+ row
+ entry
spanname=idconstantV4L2_CID_DPCM_PREDICTOR/constant/entry
+ entrymenu/entry
+ /row
+ row id=v4l2-dpcm-predictor
+ entry spanname=descr Differential pulse-code modulation (DPCM)
is a signal
+ encoder that uses the baseline of pulse-code modulation (PCM) but
adds some
+ functionalities based on the prediction of the samples of the
signal. The input
+ can be an analog signal or a digital signal.
+
+ paraIf the input is a continuous-time
+ analog signal, it needs to be sampled first so that a discrete-time
signal is
+ the input to the DPCM encoder./para
+
+ paraSimple: take the values of two
+ consecutive samples; if they are analog samples, quantize them;
calculate the
+ difference between the first one and the next; the output is the
difference, and
+ it can be further entropy coded./para
+
+ paraAdvanced: instead of taking a difference relative to a
previous input sample,
+ take the difference relative to the output of a local model of the
decoder process;
+ in this option, the difference can be quantized, which allows a
good way to
+ incorporate a controlled loss in the encoding./para
+
+ paraApplying one of these two processes, short-term redundancy
(positive correlation of
+ nearby values) of the signal is eliminated; compression ratios on
the order of 2 to 4
+ can be achieved if differences are subsequently entropy coded,
because the entropy of
+ the difference signal is much smaller than that of the original
discrete signal treated
+ as independent samples.For more information about DPCM see ulink
+
url=http://en.wikipedia.org/wiki/Differential_pulse-code_modulation;Wikipedia/ulink./para
+ /entry
+ /row
+ row
+ entrytbl spanname=descr cols=2
+ tbody valign=top
+ row
+ entryconstantV4L2_DPCM_PREDICTOR_SIMPLE/constant/entry
+ entryPredictor type is simple/entry
+ /row
+ row
+
entryconstantV4L2_DPCM_PREDICTOR_ADVANCED/constant/entry
+ entryPredictor type is advanced/entry
+ /row
+ /tbody
+ /entrytbl
+ /row
+ rowentry/entry/row
/tbody
/tgroup
/table
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index b6a2ee7..2d7bc15 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -425,6 +425,11 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
Gray,
NULL,
};
+ static const char * const dpcm_predictor[] = {
+ Simple Predictor,
+ Advanced Predictor,
+ NULL,
+ };
switch (id) {
case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
@@ -502,6 +507,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
return mpeg4_profile;
Re: [PATCH v3] media: v4l2-ctrls: add control for dpcm predictor
On 09/03/2012 09:20 AM, Prabhakar Lad wrote:
From: Lad, Prabhakar prabhakar@ti.com
add V4L2_CID_DPCM_PREDICTOR control of type menu, which
determines the dpcm predictor. The predictor can be either
simple or advanced.
Signed-off-by: Lad, Prabhakar prabhakar@ti.com
Signed-off-by: Manjunath Hadli manjunath.ha...@ti.com
Cc: Sakari Ailus sakari.ai...@iki.fi
Cc: Hans Verkuil hans.verk...@cisco.com
Cc: Laurent Pinchart laurent.pinch...@ideasonboard.com
Cc: Mauro Carvalho Chehab mche...@infradead.org
Cc: Sylwester Nawrocki s.nawro...@samsung.com
Cc: Hans de Goede hdego...@redhat.com
Cc: Kyungmin Park kyungmin.p...@samsung.com
Cc: Rob Landley r...@landley.net
Cc: HeungJun Kim riverful@samsung.com
Looks good.
Reviewed-by: Sylwester Nawrocki s.nawro...@samsung.com
---
This patches has one checkpatch warning for line over
80 characters altough it can be avoided I have kept it
for consistency.
Changes for v3:
1: Added better explanation for DPCM, pointed by Hans.
Changes for v2:
1: Added documentaion in controls.xml pointed by Sylwester.
2: Chnaged V4L2_DPCM_PREDICTOR_ADVANCE to V4L2_DPCM_PREDICTOR_ADVANCED
pointed by Sakari.
Documentation/DocBook/media/v4l/controls.xml | 48
+-
drivers/media/v4l2-core/v4l2-ctrls.c |9 +
include/linux/videodev2.h|5 +++
3 files changed, 61 insertions(+), 1 deletions(-)
diff --git a/Documentation/DocBook/media/v4l/controls.xml
b/Documentation/DocBook/media/v4l/controls.xml
index 93b9c68..f704218 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -4267,7 +4267,53 @@ interface and may change in the future./para
pixels / second.
/entry
/row
- rowentry/entry/row
+ row
+ entry
spanname=idconstantV4L2_CID_DPCM_PREDICTOR/constant/entry
+ entrymenu/entry
+ /row
+ row id=v4l2-dpcm-predictor
+ entry spanname=descr Differential pulse-code modulation (DPCM)
is a signal
+ encoder that uses the baseline of pulse-code modulation (PCM) but
adds some
+ functionalities based on the prediction of the samples of the
signal. The input
+ can be an analog signal or a digital signal.
+
+ paraIf the input is a continuous-time
+ analog signal, it needs to be sampled first so that a discrete-time
signal is
+ the input to the DPCM encoder./para
nit: this whole paragraph could fit in 2 lines.
+
+ paraSimple: take the values of two
+ consecutive samples; if they are analog samples, quantize them;
calculate the
+ difference between the first one and the next; the output is the
difference, and
+ it can be further entropy coded./para
+
+ paraAdvanced: instead of taking a difference relative to a
previous input sample,
+ take the difference relative to the output of a local model of the
decoder process;
+ in this option, the difference can be quantized, which allows a
good way to
+ incorporate a controlled loss in the encoding./para
+
+ paraApplying one of these two processes, short-term redundancy
(positive correlation of
+ nearby values) of the signal is eliminated; compression ratios on
the order of 2 to 4
+ can be achieved if differences are subsequently entropy coded,
because the entropy of
+ the difference signal is much smaller than that of the original
discrete signal treated
+ as independent samples.For more information about DPCM see ulink
+
url=http://en.wikipedia.org/wiki/Differential_pulse-code_modulation;Wikipedia/ulink./para
+ /entry
+ /row
+ row
+ entrytbl spanname=descr cols=2
+ tbody valign=top
+ row
+ entryconstantV4L2_DPCM_PREDICTOR_SIMPLE/constant/entry
+ entryPredictor type is simple/entry
+ /row
+ row
+
entryconstantV4L2_DPCM_PREDICTOR_ADVANCED/constant/entry
+ entryPredictor type is advanced/entry
+ /row
+ /tbody
+ /entrytbl
+ /row
+ rowentry/entry/row
/tbody
/tgroup
/table
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index b6a2ee7..2d7bc15 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -425,6 +425,11 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
Gray,
NULL,
};
+ static const char * const dpcm_predictor[] = {
+ Simple Predictor,
+ Advanced Predictor,
+ NULL,
+ };
switch (id) {
case V4L2_CID_MPEG_AUDIO_SAMPLING_FREQ:
@@ -502,6 +507,8 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
Re: [PATCH v3] media: v4l2-ctrls: add control for dpcm predictor
Hi Sylwester,
Thanks for the review.
On Monday 03 September 2012 02:51 PM, Sylwester Nawrocki wrote:
On 09/03/2012 09:20 AM, Prabhakar Lad wrote:
From: Lad, Prabhakar prabhakar@ti.com
add V4L2_CID_DPCM_PREDICTOR control of type menu, which
determines the dpcm predictor. The predictor can be either
simple or advanced.
Signed-off-by: Lad, Prabhakar prabhakar@ti.com
Signed-off-by: Manjunath Hadli manjunath.ha...@ti.com
Cc: Sakari Ailus sakari.ai...@iki.fi
Cc: Hans Verkuil hans.verk...@cisco.com
Cc: Laurent Pinchart laurent.pinch...@ideasonboard.com
Cc: Mauro Carvalho Chehab mche...@infradead.org
Cc: Sylwester Nawrocki s.nawro...@samsung.com
Cc: Hans de Goede hdego...@redhat.com
Cc: Kyungmin Park kyungmin.p...@samsung.com
Cc: Rob Landley r...@landley.net
Cc: HeungJun Kim riverful@samsung.com
Looks good.
Reviewed-by: Sylwester Nawrocki s.nawro...@samsung.com
---
This patches has one checkpatch warning for line over
80 characters altough it can be avoided I have kept it
for consistency.
Changes for v3:
1: Added better explanation for DPCM, pointed by Hans.
Changes for v2:
1: Added documentaion in controls.xml pointed by Sylwester.
2: Chnaged V4L2_DPCM_PREDICTOR_ADVANCE to V4L2_DPCM_PREDICTOR_ADVANCED
pointed by Sakari.
Documentation/DocBook/media/v4l/controls.xml | 48
+-
drivers/media/v4l2-core/v4l2-ctrls.c |9 +
include/linux/videodev2.h|5 +++
3 files changed, 61 insertions(+), 1 deletions(-)
diff --git a/Documentation/DocBook/media/v4l/controls.xml
b/Documentation/DocBook/media/v4l/controls.xml
index 93b9c68..f704218 100644
--- a/Documentation/DocBook/media/v4l/controls.xml
+++ b/Documentation/DocBook/media/v4l/controls.xml
@@ -4267,7 +4267,53 @@ interface and may change in the future./para
pixels / second.
/entry
/row
- rowentry/entry/row
+ row
+entry
spanname=idconstantV4L2_CID_DPCM_PREDICTOR/constant/entry
+entrymenu/entry
+ /row
+ row id=v4l2-dpcm-predictor
+entry spanname=descr Differential pulse-code modulation (DPCM)
is a signal
+encoder that uses the baseline of pulse-code modulation (PCM) but
adds some
+functionalities based on the prediction of the samples of the
signal. The input
+can be an analog signal or a digital signal.
+
+paraIf the input is a continuous-time
+analog signal, it needs to be sampled first so that a discrete-time
signal is
+the input to the DPCM encoder./para
nit: this whole paragraph could fit in 2 lines.
thanks for the catch ,I'll post a v4 fixing this.
Thanks and Regards,
--Prabhakar Lad
+
+paraSimple: take the values of two
+consecutive samples; if they are analog samples, quantize them;
calculate the
+difference between the first one and the next; the output is the
difference, and
+it can be further entropy coded./para
+
+paraAdvanced: instead of taking a difference relative to a
previous input sample,
+take the difference relative to the output of a local model of the
decoder process;
+in this option, the difference can be quantized, which allows a
good way to
+incorporate a controlled loss in the encoding./para
+
+paraApplying one of these two processes, short-term redundancy
(positive correlation of
+nearby values) of the signal is eliminated; compression ratios on
the order of 2 to 4
+can be achieved if differences are subsequently entropy coded,
because the entropy of
+the difference signal is much smaller than that of the original
discrete signal treated
+as independent samples.For more information about DPCM see ulink
+
url=http://en.wikipedia.org/wiki/Differential_pulse-code_modulation;Wikipedia/ulink./para
+/entry
+ /row
+ row
+entrytbl spanname=descr cols=2
+ tbody valign=top
+row
+ entryconstantV4L2_DPCM_PREDICTOR_SIMPLE/constant/entry
+ entryPredictor type is simple/entry
+/row
+row
+
entryconstantV4L2_DPCM_PREDICTOR_ADVANCED/constant/entry
+ entryPredictor type is advanced/entry
+/row
+ /tbody
+/entrytbl
+ /row
+rowentry/entry/row
/tbody
/tgroup
/table
diff --git a/drivers/media/v4l2-core/v4l2-ctrls.c
b/drivers/media/v4l2-core/v4l2-ctrls.c
index b6a2ee7..2d7bc15 100644
--- a/drivers/media/v4l2-core/v4l2-ctrls.c
+++ b/drivers/media/v4l2-core/v4l2-ctrls.c
@@ -425,6 +425,11 @@ const char * const *v4l2_ctrl_get_menu(u32 id)
Gray,
NULL,
};
+static const char * const dpcm_predictor[] = {
+Simple Predictor,
+Advanced Predictor,
+NULL,
+};
