/* GStreamer * Copyright (C) 2020 Seungha Yang * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include #include "gstnvvp9dec.h" #include "gstnvdecoder.h" #include GST_DEBUG_CATEGORY_STATIC (gst_nv_vp9_dec_debug); #define GST_CAT_DEFAULT gst_nv_vp9_dec_debug struct _GstNvVp9Dec { GstVp9Decoder parent; GstVideoCodecState *output_state; GstCudaContext *context; GstNvDecoder *decoder; CUVIDPICPARAMS params; guint width, height; GstVP9Profile profile; }; struct _GstNvVp9DecClass { GstVp9DecoderClass parent_class; guint cuda_device_id; }; #define gst_nv_vp9_dec_parent_class parent_class /** * GstNvVp9Dec: * * Since: 1.20 */ G_DEFINE_TYPE (GstNvVp9Dec, gst_nv_vp9_dec, GST_TYPE_VP9_DECODER); static void gst_nv_vp9_dec_set_context (GstElement * element, GstContext * context); static gboolean gst_nv_vp9_dec_open (GstVideoDecoder * decoder); static gboolean gst_nv_vp9_dec_close (GstVideoDecoder * decoder); static gboolean gst_nv_vp9_dec_negotiate (GstVideoDecoder * decoder); static gboolean gst_nv_vp9_dec_decide_allocation (GstVideoDecoder * decoder, GstQuery * query); static gboolean gst_nv_vp9_dec_src_query (GstVideoDecoder * decoder, GstQuery * query); /* GstVp9Decoder */ static GstFlowReturn gst_nv_vp9_dec_new_sequence (GstVp9Decoder * decoder, const GstVp9FrameHeader * frame_hdr, gint max_dpb_size); static GstFlowReturn gst_nv_vp9_dec_new_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture); static GstVp9Picture *gst_nv_vp9_dec_duplicate_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture); static GstFlowReturn gst_nv_vp9_dec_decode_picture (GstVp9Decoder * decoder, GstVp9Picture * picture, GstVp9Dpb * dpb); static GstFlowReturn gst_nv_vp9_dec_output_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture); static guint gst_nv_vp9_dec_get_preferred_output_delay (GstVp9Decoder * decoder, gboolean is_live); static void gst_nv_vp9_dec_class_init (GstNvVp9DecClass * klass) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); GstVideoDecoderClass *decoder_class = GST_VIDEO_DECODER_CLASS (klass); GstVp9DecoderClass *vp9decoder_class = GST_VP9_DECODER_CLASS (klass); element_class->set_context = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_set_context); decoder_class->open = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_open); decoder_class->close = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_close); decoder_class->negotiate = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_negotiate); decoder_class->decide_allocation = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_decide_allocation); decoder_class->src_query = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_src_query); vp9decoder_class->new_sequence = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_new_sequence); vp9decoder_class->new_picture = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_new_picture); vp9decoder_class->duplicate_picture = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_duplicate_picture); vp9decoder_class->decode_picture = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_decode_picture); vp9decoder_class->output_picture = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_output_picture); vp9decoder_class->get_preferred_output_delay = GST_DEBUG_FUNCPTR (gst_nv_vp9_dec_get_preferred_output_delay); GST_DEBUG_CATEGORY_INIT (gst_nv_vp9_dec_debug, "nvvp9dec", 0, "NVIDIA VP9 Decoder"); gst_type_mark_as_plugin_api (GST_TYPE_NV_VP9_DEC, 0); } static void gst_nv_vp9_dec_init (GstNvVp9Dec * self) { } static void gst_nv_vp9_dec_set_context (GstElement * element, GstContext * context) { GstNvVp9Dec *self = GST_NV_VP9_DEC (element); GstNvVp9DecClass *klass = GST_NV_VP9_DEC_GET_CLASS (self); GST_DEBUG_OBJECT (self, "set context %s", gst_context_get_context_type (context)); if (gst_cuda_handle_set_context (element, context, klass->cuda_device_id, &self->context)) { goto done; } if (self->decoder) gst_nv_decoder_handle_set_context (self->decoder, element, context); done: GST_ELEMENT_CLASS (parent_class)->set_context (element, context); } static gboolean gst_nv_vp9_dec_open (GstVideoDecoder * decoder) { GstVp9Decoder *vp9dec = GST_VP9_DECODER (decoder); GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstNvVp9DecClass *klass = GST_NV_VP9_DEC_GET_CLASS (self); if (!gst_cuda_ensure_element_context (GST_ELEMENT (self), klass->cuda_device_id, &self->context)) { GST_ERROR_OBJECT (self, "Required element data is unavailable"); return FALSE; } self->decoder = gst_nv_decoder_new (self->context); if (!self->decoder) { GST_ERROR_OBJECT (self, "Failed to create decoder object"); gst_clear_object (&self->context); return FALSE; } /* NVDEC doesn't support non-keyframe resolution change and it will result * in outputting broken frames */ gst_vp9_decoder_set_non_keyframe_format_change_support (vp9dec, FALSE); return TRUE; } static gboolean gst_nv_vp9_dec_close (GstVideoDecoder * decoder) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); g_clear_pointer (&self->output_state, gst_video_codec_state_unref); gst_clear_object (&self->decoder); gst_clear_object (&self->context); return TRUE; } static gboolean gst_nv_vp9_dec_negotiate (GstVideoDecoder * decoder) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstVp9Decoder *vp9dec = GST_VP9_DECODER (decoder); GST_DEBUG_OBJECT (self, "negotiate"); gst_nv_decoder_negotiate (self->decoder, decoder, vp9dec->input_state, &self->output_state); /* TODO: add support D3D11 memory */ return GST_VIDEO_DECODER_CLASS (parent_class)->negotiate (decoder); } static gboolean gst_nv_vp9_dec_decide_allocation (GstVideoDecoder * decoder, GstQuery * query) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); if (!gst_nv_decoder_decide_allocation (self->decoder, decoder, query)) { GST_WARNING_OBJECT (self, "Failed to handle decide allocation"); return FALSE; } return GST_VIDEO_DECODER_CLASS (parent_class)->decide_allocation (decoder, query); } static gboolean gst_nv_vp9_dec_src_query (GstVideoDecoder * decoder, GstQuery * query) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); switch (GST_QUERY_TYPE (query)) { case GST_QUERY_CONTEXT: if (gst_cuda_handle_context_query (GST_ELEMENT (decoder), query, self->context)) { return TRUE; } else if (self->decoder && gst_nv_decoder_handle_context_query (self->decoder, decoder, query)) { return TRUE; } break; default: break; } return GST_VIDEO_DECODER_CLASS (parent_class)->src_query (decoder, query); } static GstFlowReturn gst_nv_vp9_dec_new_sequence (GstVp9Decoder * decoder, const GstVp9FrameHeader * frame_hdr, gint max_dpb_size) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstVideoFormat out_format = GST_VIDEO_FORMAT_UNKNOWN; GstVideoInfo info; GST_LOG_OBJECT (self, "new sequence"); self->width = frame_hdr->width; self->height = frame_hdr->height; self->profile = frame_hdr->profile; if (self->profile == GST_VP9_PROFILE_0) { out_format = GST_VIDEO_FORMAT_NV12; } else if (self->profile == GST_VP9_PROFILE_2) { if (frame_hdr->bit_depth == 10) { out_format = GST_VIDEO_FORMAT_P010_10LE; } else { out_format = GST_VIDEO_FORMAT_P016_LE; } } if (out_format == GST_VIDEO_FORMAT_UNKNOWN) { GST_ERROR_OBJECT (self, "Could not support profile %d", self->profile); return GST_FLOW_NOT_NEGOTIATED; } gst_video_info_set_format (&info, out_format, self->width, self->height); if (!gst_nv_decoder_configure (self->decoder, cudaVideoCodec_VP9, &info, self->width, self->height, frame_hdr->bit_depth, max_dpb_size, FALSE)) { GST_ERROR_OBJECT (self, "Failed to configure decoder"); return GST_FLOW_NOT_NEGOTIATED; } if (!gst_video_decoder_negotiate (GST_VIDEO_DECODER (self))) { GST_ERROR_OBJECT (self, "Failed to negotiate with downstream"); return GST_FLOW_NOT_NEGOTIATED; } memset (&self->params, 0, sizeof (CUVIDPICPARAMS)); self->params.CodecSpecific.vp9.colorSpace = frame_hdr->color_space; return GST_FLOW_OK; } static GstFlowReturn gst_nv_vp9_dec_new_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstNvDecoderFrame *nv_frame; nv_frame = gst_nv_decoder_new_frame (self->decoder); if (!nv_frame) { GST_ERROR_OBJECT (self, "No available decoder frame"); return GST_FLOW_ERROR; } GST_LOG_OBJECT (self, "New decoder frame %p (index %d)", nv_frame, nv_frame->index); gst_vp9_picture_set_user_data (picture, nv_frame, (GDestroyNotify) gst_nv_decoder_frame_unref); return GST_FLOW_OK; } static GstNvDecoderFrame * gst_nv_vp9_dec_get_decoder_frame_from_picture (GstNvVp9Dec * self, GstVp9Picture * picture) { GstNvDecoderFrame *frame; frame = (GstNvDecoderFrame *) gst_vp9_picture_get_user_data (picture); if (!frame) GST_DEBUG_OBJECT (self, "current picture does not have decoder frame"); return frame; } static GstVp9Picture * gst_nv_vp9_dec_duplicate_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstNvDecoderFrame *nv_frame; GstVp9Picture *new_picture; nv_frame = gst_nv_vp9_dec_get_decoder_frame_from_picture (self, picture); if (!nv_frame) { GST_ERROR_OBJECT (self, "Parent picture does not have decoder frame"); return NULL; } new_picture = gst_vp9_picture_new (); new_picture->frame_hdr = picture->frame_hdr; gst_vp9_picture_set_user_data (new_picture, gst_nv_decoder_frame_ref (nv_frame), (GDestroyNotify) gst_nv_decoder_frame_unref); return new_picture; } static GstFlowReturn gst_nv_vp9_dec_decode_picture (GstVp9Decoder * decoder, GstVp9Picture * picture, GstVp9Dpb * dpb) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); const GstVp9FrameHeader *frame_hdr = &picture->frame_hdr; const GstVp9LoopFilterParams *lfp = &frame_hdr->loop_filter_params; const GstVp9SegmentationParams *sp = &frame_hdr->segmentation_params; const GstVp9QuantizationParams *qp = &frame_hdr->quantization_params; CUVIDPICPARAMS *params = &self->params; CUVIDVP9PICPARAMS *vp9_params = ¶ms->CodecSpecific.vp9; GstNvDecoderFrame *frame; GstNvDecoderFrame *other_frame; guint offset = 0; guint8 ref_frame_map[GST_VP9_REF_FRAMES]; gint i; G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->mbRefLfDelta) == GST_VP9_MAX_REF_LF_DELTAS); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->mbModeLfDelta) == GST_VP9_MAX_MODE_LF_DELTAS); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->mb_segment_tree_probs) == GST_VP9_SEG_TREE_PROBS); G_STATIC_ASSERT (sizeof (vp9_params->mb_segment_tree_probs) == sizeof (sp->segmentation_tree_probs)); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->segment_pred_probs) == GST_VP9_PREDICTION_PROBS); G_STATIC_ASSERT (sizeof (vp9_params->segment_pred_probs) == sizeof (sp->segmentation_pred_prob)); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->refFrameSignBias) == GST_VP9_REFS_PER_FRAME + 1); G_STATIC_ASSERT (sizeof (vp9_params->refFrameSignBias) == sizeof (frame_hdr->ref_frame_sign_bias)); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->activeRefIdx) == GST_VP9_REFS_PER_FRAME); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->segmentFeatureEnable) == GST_VP9_MAX_SEGMENTS); G_STATIC_ASSERT (sizeof (vp9_params->segmentFeatureEnable) == sizeof (sp->feature_enabled)); G_STATIC_ASSERT (G_N_ELEMENTS (vp9_params->segmentFeatureData) == GST_VP9_MAX_SEGMENTS); G_STATIC_ASSERT (sizeof (vp9_params->segmentFeatureData) == sizeof (sp->feature_data)); GST_LOG_OBJECT (self, "Decode picture, size %" G_GSIZE_FORMAT, picture->size); frame = gst_nv_vp9_dec_get_decoder_frame_from_picture (self, picture); if (!frame) { GST_ERROR_OBJECT (self, "Decoder frame is unavailable"); return GST_FLOW_ERROR; } params->nBitstreamDataLen = picture->size; params->pBitstreamData = picture->data; params->nNumSlices = 1; params->pSliceDataOffsets = &offset; params->PicWidthInMbs = GST_ROUND_UP_16 (frame_hdr->width) >> 4; params->FrameHeightInMbs = GST_ROUND_UP_16 (frame_hdr->height) >> 4; params->CurrPicIdx = frame->index; vp9_params->width = frame_hdr->width; vp9_params->height = frame_hdr->height; for (i = 0; i < GST_VP9_REF_FRAMES; i++) { if (dpb->pic_list[i]) { other_frame = gst_nv_vp9_dec_get_decoder_frame_from_picture (self, dpb->pic_list[i]); if (!other_frame) { GST_ERROR_OBJECT (self, "Couldn't get decoder frame from picture"); return FALSE; } ref_frame_map[i] = other_frame->index; } else { ref_frame_map[i] = 0xff; } } vp9_params->LastRefIdx = ref_frame_map[frame_hdr->ref_frame_idx[0]]; vp9_params->GoldenRefIdx = ref_frame_map[frame_hdr->ref_frame_idx[1]]; vp9_params->AltRefIdx = ref_frame_map[frame_hdr->ref_frame_idx[2]]; vp9_params->profile = frame_hdr->profile; vp9_params->frameContextIdx = frame_hdr->frame_context_idx; vp9_params->frameType = frame_hdr->frame_type; vp9_params->showFrame = frame_hdr->show_frame; vp9_params->errorResilient = frame_hdr->error_resilient_mode; vp9_params->frameParallelDecoding = frame_hdr->frame_parallel_decoding_mode; vp9_params->subSamplingX = frame_hdr->subsampling_x; vp9_params->subSamplingY = frame_hdr->subsampling_y; vp9_params->intraOnly = frame_hdr->intra_only; vp9_params->allow_high_precision_mv = frame_hdr->allow_high_precision_mv; vp9_params->refreshEntropyProbs = frame_hdr->refresh_frame_context; vp9_params->bitDepthMinus8Luma = frame_hdr->bit_depth - 8; vp9_params->bitDepthMinus8Chroma = frame_hdr->bit_depth - 8; vp9_params->loopFilterLevel = lfp->loop_filter_level; vp9_params->loopFilterSharpness = lfp->loop_filter_sharpness; vp9_params->modeRefLfEnabled = lfp->loop_filter_delta_enabled; vp9_params->log2_tile_columns = frame_hdr->tile_cols_log2; vp9_params->log2_tile_rows = frame_hdr->tile_rows_log2; vp9_params->segmentEnabled = sp->segmentation_enabled; vp9_params->segmentMapUpdate = sp->segmentation_update_map; vp9_params->segmentMapTemporalUpdate = sp->segmentation_temporal_update; vp9_params->segmentFeatureMode = sp->segmentation_abs_or_delta_update; vp9_params->qpYAc = qp->base_q_idx; vp9_params->qpYDc = qp->delta_q_y_dc; vp9_params->qpChDc = qp->delta_q_uv_dc; vp9_params->qpChAc = qp->delta_q_uv_ac; vp9_params->resetFrameContext = frame_hdr->reset_frame_context; vp9_params->mcomp_filter_type = frame_hdr->interpolation_filter; vp9_params->frameTagSize = frame_hdr->frame_header_length_in_bytes; vp9_params->offsetToDctParts = frame_hdr->header_size_in_bytes; for (i = 0; i < GST_VP9_MAX_REF_LF_DELTAS; i++) vp9_params->mbRefLfDelta[i] = lfp->loop_filter_ref_deltas[i]; for (i = 0; i < GST_VP9_MAX_MODE_LF_DELTAS; i++) vp9_params->mbModeLfDelta[i] = lfp->loop_filter_mode_deltas[i]; memcpy (vp9_params->mb_segment_tree_probs, sp->segmentation_tree_probs, sizeof (sp->segmentation_tree_probs)); memcpy (vp9_params->segment_pred_probs, sp->segmentation_pred_prob, sizeof (sp->segmentation_pred_prob)); memcpy (vp9_params->refFrameSignBias, frame_hdr->ref_frame_sign_bias, sizeof (frame_hdr->ref_frame_sign_bias)); for (i = 0; i < GST_VP9_REFS_PER_FRAME; i++) { vp9_params->activeRefIdx[i] = frame_hdr->ref_frame_idx[i]; } memcpy (vp9_params->segmentFeatureEnable, sp->feature_enabled, sizeof (sp->feature_enabled)); memcpy (vp9_params->segmentFeatureData, sp->feature_data, sizeof (sp->feature_data)); if (!gst_nv_decoder_decode_picture (self->decoder, &self->params)) return GST_FLOW_ERROR; return GST_FLOW_OK; } static GstFlowReturn gst_nv_vp9_dec_output_picture (GstVp9Decoder * decoder, GstVideoCodecFrame * frame, GstVp9Picture * picture) { GstNvVp9Dec *self = GST_NV_VP9_DEC (decoder); GstVideoDecoder *vdec = GST_VIDEO_DECODER (decoder); GstNvDecoderFrame *decoder_frame; GST_LOG_OBJECT (self, "Outputting picture %p", picture); decoder_frame = (GstNvDecoderFrame *) gst_vp9_picture_get_user_data (picture); if (!decoder_frame) { GST_ERROR_OBJECT (self, "No decoder frame in picture %p", picture); goto error; } if (!gst_nv_decoder_finish_frame (self->decoder, vdec, decoder_frame, &frame->output_buffer)) { GST_ERROR_OBJECT (self, "Failed to handle output picture"); goto error; } gst_vp9_picture_unref (picture); return gst_video_decoder_finish_frame (vdec, frame); error: gst_video_decoder_drop_frame (vdec, frame); gst_vp9_picture_unref (picture); return GST_FLOW_ERROR; } static guint gst_nv_vp9_dec_get_preferred_output_delay (GstVp9Decoder * decoder, gboolean is_live) { /* Prefer to zero latency for live pipeline */ if (is_live) return 0; /* NVCODEC SDK uses 4 frame delay for better throughput performance */ return 4; } typedef struct { GstCaps *sink_caps; GstCaps *src_caps; guint cuda_device_id; gboolean is_default; } GstNvVp9DecClassData; static void gst_nv_vp9_dec_subclass_init (gpointer klass, GstNvVp9DecClassData * cdata) { GstElementClass *element_class = GST_ELEMENT_CLASS (klass); GstNvVp9DecClass *nvdec_class = (GstNvVp9DecClass *) (klass); gchar *long_name; if (cdata->is_default) { long_name = g_strdup_printf ("NVDEC VP9 Stateless Decoder"); } else { long_name = g_strdup_printf ("NVDEC VP9 Stateless Decoder with device %d", cdata->cuda_device_id); } gst_element_class_set_metadata (element_class, long_name, "Codec/Decoder/Video/Hardware", "NVIDIA VP9 video decoder", "Seungha Yang "); g_free (long_name); gst_element_class_add_pad_template (element_class, gst_pad_template_new ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, cdata->sink_caps)); gst_element_class_add_pad_template (element_class, gst_pad_template_new ("src", GST_PAD_SRC, GST_PAD_ALWAYS, cdata->src_caps)); nvdec_class->cuda_device_id = cdata->cuda_device_id; gst_caps_unref (cdata->sink_caps); gst_caps_unref (cdata->src_caps); g_free (cdata); } void gst_nv_vp9_dec_register (GstPlugin * plugin, guint device_id, guint rank, GstCaps * sink_caps, GstCaps * src_caps, gboolean is_primary) { GTypeQuery type_query; GTypeInfo type_info = { 0, }; GType subtype; gchar *type_name; gchar *feature_name; GstNvVp9DecClassData *cdata; gboolean is_default = TRUE; /** * element-nvvp9sldec: * * Since: 1.20 */ cdata = g_new0 (GstNvVp9DecClassData, 1); cdata->sink_caps = gst_caps_copy (sink_caps); gst_caps_set_simple (cdata->sink_caps, "alignment", G_TYPE_STRING, "frame", NULL); GST_MINI_OBJECT_FLAG_SET (cdata->sink_caps, GST_MINI_OBJECT_FLAG_MAY_BE_LEAKED); cdata->src_caps = gst_caps_ref (src_caps); cdata->cuda_device_id = device_id; g_type_query (GST_TYPE_NV_VP9_DEC, &type_query); memset (&type_info, 0, sizeof (type_info)); type_info.class_size = type_query.class_size; type_info.instance_size = type_query.instance_size; type_info.class_init = (GClassInitFunc) gst_nv_vp9_dec_subclass_init; type_info.class_data = cdata; if (is_primary) { type_name = g_strdup ("GstNvVP9StatelessPrimaryDec"); feature_name = g_strdup ("nvvp9dec"); } else { type_name = g_strdup ("GstNvVP9StatelessDec"); feature_name = g_strdup ("nvvp9sldec"); } if (g_type_from_name (type_name) != 0) { g_free (type_name); g_free (feature_name); if (is_primary) { type_name = g_strdup_printf ("GstNvVP9StatelessPrimaryDevice%dDec", device_id); feature_name = g_strdup_printf ("nvvp9device%ddec", device_id); } else { type_name = g_strdup_printf ("GstNvVP9StatelessDevice%dDec", device_id); feature_name = g_strdup_printf ("nvvp9sldevice%ddec", device_id); } is_default = FALSE; } cdata->is_default = is_default; subtype = g_type_register_static (GST_TYPE_NV_VP9_DEC, type_name, &type_info, 0); /* make lower rank than default device */ if (rank > 0 && !is_default) rank--; if (!gst_element_register (plugin, feature_name, rank, subtype)) GST_WARNING ("Failed to register plugin '%s'", type_name); g_free (type_name); g_free (feature_name); }