[libcamera-devel,v2,07/10] pipeline: raspberrypi: Add a parameter to disable startup drop frames

17914 diff mbox series

Add a new pipeline config parameter "disable_startup_frame_drops" to disable
any startup drop frames, overriding the IPA request.

When this parameter is set, it allows the pipeline handler to run with no
internally allocated Unicam buffers ("min_unicam_buffers").

Add a validation to ensure if "disable_startup_frame_drops" is false, at least
one internal Unicam buffer is allocated, possibly overriding the
"min_unicam_buffers" parameter.

Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
---
 .../pipeline/raspberrypi/data/default.json    |  7 +++++--
 .../pipeline/raspberrypi/raspberrypi.cpp      | 19 ++++++++++++++++++-
 2 files changed, 23 insertions(+), 3 deletions(-)

Hi Naush,

Thank you for the patch.

On Tue, Nov 29, 2022 at 01:45:31PM +0000, Naushir Patuck via libcamera-devel wrote:
> Add a new pipeline config parameter "disable_startup_frame_drops" to disable
> any startup drop frames, overriding the IPA request.
> 
> When this parameter is set, it allows the pipeline handler to run with no
> internally allocated Unicam buffers ("min_unicam_buffers").
> 
> Add a validation to ensure if "disable_startup_frame_drops" is false, at least
> one internal Unicam buffer is allocated, possibly overriding the
> "min_unicam_buffers" parameter.

Is this meant to support applications that want to capture all frames,
or only as a side effect of the memory allocation optimizations to lower
memory consumption ? In the latter case, as mentioned in the review of
06/10, I don't think this would be required.

> Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
> Reviewed-by: David Plowman <david.plowman@raspberrypi.com>
> ---
>  .../pipeline/raspberrypi/data/default.json    |  7 +++++--
>  .../pipeline/raspberrypi/raspberrypi.cpp      | 19 ++++++++++++++++++-
>  2 files changed, 23 insertions(+), 3 deletions(-)
> 
> diff --git a/src/libcamera/pipeline/raspberrypi/data/default.json b/src/libcamera/pipeline/raspberrypi/data/default.json
> index a7ea735c87f4..707414bcc5c5 100644
> --- a/src/libcamera/pipeline/raspberrypi/data/default.json
> +++ b/src/libcamera/pipeline/raspberrypi/data/default.json
> @@ -5,7 +5,7 @@
>          "pipeline_handler":
>          {
>                  # The minimum number of internal buffers to be allocated for Unicam.
> -                # This value must be greater than 0, but less than or equal to min_total_unicam_buffers.
> +                # This value must less than or equal to min_total_unicam_buffers.
>                  "min_unicam_buffers": 2,
>  
>                  # The minimum total (internal + external) buffer count used for Unicam.
> @@ -15,6 +15,9 @@
>                  "min_total_unicam_buffers": 4,
>                  
>                  # The number of internal buffers used for ISP Output0.
> -                "num_output0_buffers": 1
> +                "num_output0_buffers": 1,
> +
> +                # Override any request from the IPA to drop a number of startup frames.
> +                "disable_startup_frame_drops": false
>          }
>  }
> diff --git a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> index 742521927780..ef49d32037af 100644
> --- a/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> +++ b/src/libcamera/pipeline/raspberrypi/raspberrypi.cpp
> @@ -312,6 +312,11 @@ public:
>  		 * stream.
>  		 */
>  		unsigned int numOutput0Buffers;
> +		/*
> +		 * Override any request from the IPA to drop a number of startup
> +		 * frames.
> +		 */
> +		bool disableStartupFrameDrops;
>  	};
>  
>  	Config config_;
> @@ -1058,7 +1063,7 @@ int PipelineHandlerRPi::start(Camera *camera, const ControlList *controls)
>  		data->setSensorControls(startConfig.controls);
>  
>  	/* Configure the number of dropped frames required on startup. */
> -	data->dropFrameCount_ = startConfig.dropFrameCount;
> +	data->dropFrameCount_ = data->config_.disableStartupFrameDrops ? 0 : startConfig.dropFrameCount;
>  
>  	for (auto const stream : data->streams_)
>  		stream->resetBuffers();
> @@ -1451,6 +1456,7 @@ int PipelineHandlerRPi::configurePipelineHandler(RPiCameraData *data)
>  		.minUnicamBuffers = 2,
>  		.minTotalUnicamBuffers = 4,
>  		.numOutput0Buffers = 1,
> +		.disableStartupFrameDrops = false,
>  	};
>  
>  	char const *configFromEnv = utils::secure_getenv("LIBCAMERA_RPI_CONFIG_FILE");
> @@ -1485,6 +1491,8 @@ int PipelineHandlerRPi::configurePipelineHandler(RPiCameraData *data)
>  		phConfig["min_total_unicam_buffers"].get<unsigned int>(config.minTotalUnicamBuffers);
>  	config.numOutput0Buffers =
>  		phConfig["num_output0_buffers"].get<unsigned int>(config.numOutput0Buffers);
> +	config.disableStartupFrameDrops =
> +		phConfig["disable_startup_frame_drops"].get<bool>(config.disableStartupFrameDrops);
>  
>  	if (config.minTotalUnicamBuffers < config.minUnicamBuffers) {
>  		LOG(RPI, Error) << "Invalid configuration: min_total_unicam_buffers must be >= min_unicam_buffers!";
> @@ -1569,6 +1577,15 @@ int PipelineHandlerRPi::prepareBuffers(Camera *camera)
>  			 */
>  			numBuffers = std::max<int>(data->config_.minUnicamBuffers,
>  						   minBuffers - numRawBuffers);
> +
> +			if (numBuffers == 0 && data->dropFrameCount_) {
> +				LOG(RPI, Warning)
> +					<< "Configured with no Unicam buffers,"
> +					   " but the IPA requested startup frame drops."
> +					   " Increasing to one buffer.";
> +				numBuffers = 1;
> +			}
> +
>  			data->numUnicamBuffers = numBuffers;
>  		} else if (stream == &data->isp_[Isp::Input]) {
>  			/*