gstreamer: Factor out video pool creation

The gst_libcamera_src_negotiate() function uses 5 indentation levels,
causing long lines. Move video pool creation to a separate function to
increase readability.

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Nicolas Dufresne <nicolas.dufresne@collabora.com>
This commit is contained in:
Laurent Pinchart 2025-05-22 11:47:29 +02:00
parent 04e7823eb2
commit 3b68207789

View file

@ -29,6 +29,7 @@
#include <atomic>
#include <queue>
#include <tuple>
#include <vector>
#include <libcamera/camera.h>
@ -521,6 +522,71 @@ gst_libcamera_src_open(GstLibcameraSrc *self)
return true;
}
/**
* \brief Create a video pool for a pad
* \param[in] self The libcamerasrc instance
* \param[in] srcpad The pad
* \param[in] caps The pad caps
* \param[in] info The video info for the pad
*
* This function creates and returns a video buffer pool for the given pad if
* needed to accommodate stride mismatch. If the peer element supports stride
* negotiation through the meta API, no pool is needed and the function will
* return a null pool.
*
* \return A tuple containing the video buffers pool pointer and an error code
*/
static std::tuple<GstBufferPool *, int>
gst_libcamera_create_video_pool(GstLibcameraSrc *self, GstPad *srcpad,
GstCaps *caps, const GstVideoInfo *info)
{
GstQuery *query = NULL;
const gboolean need_pool = true;
gboolean has_video_meta = false;
GstBufferPool *video_pool = NULL;
query = gst_query_new_allocation(caps, need_pool);
if (!gst_pad_peer_query(srcpad, query))
GST_DEBUG_OBJECT(self, "Didn't get downstream ALLOCATION hints");
else
has_video_meta = gst_query_find_allocation_meta(query, GST_VIDEO_META_API_TYPE, NULL);
if (!has_video_meta) {
GstBufferPool *pool = NULL;
if (gst_query_get_n_allocation_pools(query) > 0)
gst_query_parse_nth_allocation_pool(query, 0, &pool, NULL, NULL, NULL);
if (pool)
video_pool = pool;
else {
GstStructure *config;
guint min_buffers = 3;
video_pool = gst_video_buffer_pool_new();
config = gst_buffer_pool_get_config(video_pool);
gst_buffer_pool_config_set_params(config, caps, info->size, min_buffers, 0);
GST_DEBUG_OBJECT(self, "Own pool config is %" GST_PTR_FORMAT, config);
gst_buffer_pool_set_config(GST_BUFFER_POOL_CAST(video_pool), config);
}
GST_WARNING_OBJECT(self, "Downstream doesn't support video meta, need to copy frame.");
if (!gst_buffer_pool_set_active(video_pool, true)) {
gst_caps_unref(caps);
GST_ELEMENT_ERROR(self, RESOURCE, SETTINGS,
("Failed to active buffer pool"),
("gst_libcamera_src_negotiate() failed."));
return { NULL, -EINVAL };
}
}
gst_query_unref(query);
return { video_pool, 0 };
}
/* Must be called with stream_lock held. */
static bool
gst_libcamera_src_negotiate(GstLibcameraSrc *self)
@ -603,50 +669,13 @@ gst_libcamera_src_negotiate(GstLibcameraSrc *self)
/* Stride mismatch between camera stride and that calculated by video-info. */
if (static_cast<unsigned int>(info.stride[0]) != stream_cfg.stride &&
GST_VIDEO_INFO_FORMAT(&info) != GST_VIDEO_FORMAT_ENCODED) {
GstQuery *query = NULL;
const gboolean need_pool = true;
gboolean has_video_meta = false;
gst_libcamera_extrapolate_info(&info, stream_cfg.stride);
query = gst_query_new_allocation(caps, need_pool);
if (!gst_pad_peer_query(srcpad, query))
GST_DEBUG_OBJECT(self, "Didn't get downstream ALLOCATION hints");
else
has_video_meta = gst_query_find_allocation_meta(query, GST_VIDEO_META_API_TYPE, NULL);
if (!has_video_meta) {
GstBufferPool *pool = NULL;
if (gst_query_get_n_allocation_pools(query) > 0)
gst_query_parse_nth_allocation_pool(query, 0, &pool, NULL, NULL, NULL);
if (pool)
video_pool = pool;
else {
GstStructure *config;
guint min_buffers = 3;
video_pool = gst_video_buffer_pool_new();
config = gst_buffer_pool_get_config(video_pool);
gst_buffer_pool_config_set_params(config, caps, info.size, min_buffers, 0);
GST_DEBUG_OBJECT(self, "Own pool config is %" GST_PTR_FORMAT, config);
gst_buffer_pool_set_config(GST_BUFFER_POOL_CAST(video_pool), config);
}
GST_WARNING_OBJECT(self, "Downstream doesn't support video meta, need to copy frame.");
if (!gst_buffer_pool_set_active(video_pool, true)) {
gst_caps_unref(caps);
GST_ELEMENT_ERROR(self, RESOURCE, SETTINGS,
("Failed to active buffer pool"),
("gst_libcamera_src_negotiate() failed."));
return false;
}
}
gst_query_unref(query);
std::tie(video_pool, ret) =
gst_libcamera_create_video_pool(self, srcpad,
caps, &info);
if (ret)
return false;
}
GstLibcameraPool *pool = gst_libcamera_pool_new(self->allocator,