[libcamera-devel] [PATCH 11/17] libcamera: stream: Add StreamFormats
Niklas Söderlund
niklas.soderlund at ragnatech.se
Mon May 27 02:15:37 CEST 2019
Add a StreamFormats which describes all the formats a stream can
support. The object does not collect any formation itself but can
simplify users interaction with formats as it's able to translate a
stream format range into discrete list and a discrete list to a range.
Signed-off-by: Niklas Söderlund <niklas.soderlund at ragnatech.se>
---
include/libcamera/stream.h | 16 +++
src/libcamera/stream.cpp | 216 +++++++++++++++++++++++++++++++++++++
2 files changed, 232 insertions(+)
diff --git a/include/libcamera/stream.h b/include/libcamera/stream.h
index e38c0e7e827d5888..48daf5ac23f55d85 100644
--- a/include/libcamera/stream.h
+++ b/include/libcamera/stream.h
@@ -7,6 +7,7 @@
#ifndef __LIBCAMERA_STREAM_H__
#define __LIBCAMERA_STREAM_H__
+#include <map>
#include <string>
#include <vector>
@@ -18,6 +19,21 @@ namespace libcamera {
class Camera;
class Stream;
+class StreamFormats
+{
+public:
+ StreamFormats();
+ StreamFormats(const std::map<unsigned int, std::vector<SizeRange>> &formats);
+
+ std::vector<unsigned int> pixelformats() const;
+ std::vector<Size> sizes(unsigned int pixelformat) const;
+
+ SizeRange range(unsigned int pixelformat) const;
+
+private:
+ std::map<unsigned int, std::vector<SizeRange>> formats_;
+};
+
struct StreamConfiguration {
StreamConfiguration()
: stream_(nullptr)
diff --git a/src/libcamera/stream.cpp b/src/libcamera/stream.cpp
index eecd37160150d55c..a2931902fda2baa5 100644
--- a/src/libcamera/stream.cpp
+++ b/src/libcamera/stream.cpp
@@ -7,6 +7,7 @@
#include <libcamera/stream.h>
+#include <algorithm>
#include <iomanip>
#include <sstream>
@@ -36,6 +37,221 @@ namespace libcamera {
LOG_DEFINE_CATEGORY(Stream)
+/**
+ * \class StreamFormats
+ * \brief Hold information about supported stream formats
+ *
+ * The StreamFormats class holds information about pixel formats and frame
+ * sizes a stream supports. The class groups size information by the pixel
+ * format which can produce it. There are two ways to examine the size
+ * information, as a range or as a list of discrete sizes.
+ *
+ * When sizes are viewed as a range it describes the minimum and maximum width
+ * and height values. There is a possibility to supplement the range description
+ * with a horizontal och vertical stepping size. The stepping size describes the
+ * step size in pixel from the minimum with/height.
+ *
+ * When sizes is viewed as a list of discrete sizes it describes exact dimensions
+ * which can be selected and used.
+ *
+ * Pipeline handlers can create StreamFormats describing each pixel format using
+ * either a range or a list of discrete sizes. The StreamFormats class attempts
+ * to translates between the two different ways to view them. The translations
+ * are performed as:
+ *
+ * - If a pixel format is described as a list of discrete sizes a range is
+ * created by taking the minim and maximum width/height in the list.
+ * The stepping information is not recreated and set to 1.
+ *
+ * - If a pixel format is described as a range a list of discrete sizes which
+ * fits inside that range are selected from a list of common sizes. The
+ * stepping information is taken into consideration when generating the
+ * sizes.
+ *
+ * Applications examining sizes as a range with stepping values of 1 should be
+ * aware that the range could be generated form a list of discrete sizes and
+ * there could be big gaps in the range to what the stream can support.
+ *
+ * All sizes retrieved from StreamFormats should be treated as advisory and no
+ * size should be considered to be supported until its been verified using
+ * CameraConfiguration::validate().
+ */
+
+/**
+ * \brief Construct a empty StreamFormats object
+ */
+StreamFormats::StreamFormats()
+{
+}
+
+/**
+ * \brief Construct a StreamFormats object
+ * \param[in] formats A map of pixel formats to a sizes description
+ */
+StreamFormats::StreamFormats(const std::map<unsigned int, std::vector<SizeRange>> &formats)
+ : formats_(formats)
+{
+}
+
+/**
+ * \brief Retrieve the list of pixel formats supported
+ * \returns List of pixel formats
+ */
+std::vector<unsigned int> StreamFormats::pixelformats() const
+{
+ std::vector<unsigned int> formats;
+
+ for (auto const &it : formats_)
+ formats.push_back(it.first);
+
+ return formats;
+}
+
+/**
+ * \brief Retrieve the list of frame sizes
+ * \param[in] pixelformat Pixel format to retrieve sizes for
+ * \returns List description of frame sizes
+ */
+std::vector<Size> StreamFormats::sizes(unsigned int pixelformat) const
+{
+ /*
+ * Sizes to try and extract from ranges.
+ * \todo Verify list of resolutions are good, current list compiled
+ * from v4l2 documentation and source code as well as lists of
+ * common frame sizes.
+ */
+ static const std::vector<Size> rangeDiscreteSizes = {
+ Size(160, 120),
+ Size(240, 160),
+ Size(320, 240),
+ Size(400, 240),
+ Size(480, 320),
+ Size(640, 360),
+ Size(640, 480),
+ Size(720, 480),
+ Size(720, 576),
+ Size(768, 480),
+ Size(800, 600),
+ Size(854, 480),
+ Size(960, 540),
+ Size(960, 640),
+ Size(1024, 576),
+ Size(1024, 600),
+ Size(1024, 768),
+ Size(1152, 864),
+ Size(1280, 1024),
+ Size(1280, 1080),
+ Size(1280, 720),
+ Size(1280, 800),
+ Size(1360, 768),
+ Size(1366, 768),
+ Size(1400, 1050),
+ Size(1440, 900),
+ Size(1536, 864),
+ Size(1600, 1200),
+ Size(1600, 900),
+ Size(1680, 1050),
+ Size(1920, 1080),
+ Size(1920, 1200),
+ Size(2048, 1080),
+ Size(2048, 1152),
+ Size(2048, 1536),
+ Size(2160, 1080),
+ Size(2560, 1080),
+ Size(2560, 1440),
+ Size(2560, 1600),
+ Size(2560, 2048),
+ Size(2960, 1440),
+ Size(3200, 1800),
+ Size(3200, 2048),
+ Size(3200, 2400),
+ Size(3440, 1440),
+ Size(3840, 1080),
+ Size(3840, 1600),
+ Size(3840, 2160),
+ Size(3840, 2400),
+ Size(4096, 2160),
+ Size(5120, 2160),
+ Size(5120, 2880),
+ Size(7680, 4320),
+ };
+ std::vector<Size> sizes;
+
+ /* Make sure pixel format exists. */
+ auto const &it = formats_.find(pixelformat);
+ if (it == formats_.end())
+ return {};
+
+ /* Try create list of discrete sizes. */
+ const std::vector<SizeRange> &ranges = it->second;
+ bool discrete = true;
+ for (const SizeRange &range : ranges) {
+ if (range.min != range.max) {
+ discrete = false;
+ break;
+ }
+ sizes.emplace_back(range.min.width, range.min.height);
+ }
+
+ /* If discrete not possible generate from range. */
+ if (!discrete) {
+ if (ranges.size() != 1) {
+ LOG(Stream, Error) << "Range format is ambiguous";
+ return {};
+ }
+
+ const SizeRange &limit = ranges.front();
+ sizes.clear();
+
+ for (const Size &size : rangeDiscreteSizes) {
+ if (size.width < limit.min.width ||
+ size.width > limit.max.width ||
+ size.height < limit.min.height ||
+ size.height > limit.max.height ||
+ (size.width - limit.min.width) % limit.vStep ||
+ (size.height - limit.min.height) % limit.hStep)
+ continue;
+
+ sizes.push_back(size);
+ }
+ }
+
+ std::sort(sizes.begin(), sizes.end());
+
+ return sizes;
+}
+
+/**
+ * \brief Retrieve a frame size range
+ * \param[in] pixelformat Pixel format to retrieve range for
+ * \returns Range description of frame size
+ */
+SizeRange StreamFormats::range(unsigned int pixelformat) const
+{
+ auto const it = formats_.find(pixelformat);
+ if (it == formats_.end())
+ return {};
+
+ const SizeRange &first = it->second.front();
+ if (it->second.size() == 1)
+ return first;
+
+ LOG(Stream, Debug) << "Building range from discret";
+
+ SizeRange range(first.min.width, first.min.height,
+ first.max.width, first.max.height);
+
+ for (const SizeRange &limit : it->second) {
+ if (limit.min < range.min)
+ range.min = limit.min;
+
+ if (limit.max > range.max)
+ range.max = limit.max;
+ }
+
+ return range;
+}
+
/**
* \struct StreamConfiguration
* \brief Configuration parameters for a stream
--
2.21.0
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