gstreamer/sys/nvcodec/gstnvenc.c

/* GStreamer NVENC plugin
 * Copyright (C) 2015 Centricular Ltd
 *
 * 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 "gstnvenc.h"
#include "gstnvh264enc.h"
#include "gstnvh265enc.h"
#include <gmodule.h>

#if HAVE_NVCODEC_GST_GL
#include <gst/gl/gl.h>
#endif

#ifdef _WIN32
#ifdef _WIN64
#define NVENC_LIBRARY_NAME "nvEncodeAPI64.dll"
#else
#define NVENC_LIBRARY_NAME "nvEncodeAPI.dll"
#endif
#else
#define NVENC_LIBRARY_NAME "libnvidia-encode.so.1"
#endif

typedef NVENCSTATUS NVENCAPI
tNvEncodeAPICreateInstance (NV_ENCODE_API_FUNCTION_LIST * functionList);
tNvEncodeAPICreateInstance *nvEncodeAPICreateInstance;

GST_DEBUG_CATEGORY (gst_nvenc_debug);
#define GST_CAT_DEFAULT gst_nvenc_debug

static NV_ENCODE_API_FUNCTION_LIST nvenc_api;

NVENCSTATUS
NvEncOpenEncodeSessionEx (NV_ENC_OPEN_ENCODE_SESSION_EX_PARAMS * params,
    void **encoder)
{
  g_assert (nvenc_api.nvEncOpenEncodeSessionEx != NULL);
  return nvenc_api.nvEncOpenEncodeSessionEx (params, encoder);
}

NVENCSTATUS
NvEncDestroyEncoder (void *encoder)
{
  g_assert (nvenc_api.nvEncDestroyEncoder != NULL);
  return nvenc_api.nvEncDestroyEncoder (encoder);
}

NVENCSTATUS
NvEncGetEncodeGUIDs (void *encoder, GUID * array, uint32_t array_size,
    uint32_t * count)
{
  g_assert (nvenc_api.nvEncGetEncodeGUIDs != NULL);
  return nvenc_api.nvEncGetEncodeGUIDs (encoder, array, array_size, count);
}

NVENCSTATUS
NvEncGetEncodeProfileGUIDCount (void *encoder, GUID encodeGUID,
    uint32_t * encodeProfileGUIDCount)
{
  g_assert (nvenc_api.nvEncGetEncodeProfileGUIDCount != NULL);
  return nvenc_api.nvEncGetEncodeProfileGUIDCount (encoder, encodeGUID,
      encodeProfileGUIDCount);
}

NVENCSTATUS
NvEncGetEncodeProfileGUIDs (void *encoder, GUID encodeGUID,
    GUID * profileGUIDs, uint32_t guidArraySize, uint32_t * GUIDCount)
{
  g_assert (nvenc_api.nvEncGetEncodeProfileGUIDs != NULL);
  return nvenc_api.nvEncGetEncodeProfileGUIDs (encoder, encodeGUID,
      profileGUIDs, guidArraySize, GUIDCount);
}

NVENCSTATUS
NvEncGetInputFormats (void *encoder, GUID enc_guid,
    NV_ENC_BUFFER_FORMAT * array, uint32_t size, uint32_t * num)
{
  g_assert (nvenc_api.nvEncGetInputFormats != NULL);
  return nvenc_api.nvEncGetInputFormats (encoder, enc_guid, array, size, num);
}

NVENCSTATUS
NvEncGetEncodePresetCount (void *encoder, GUID encodeGUID,
    uint32_t * encodePresetGUIDCount)
{
  g_assert (nvenc_api.nvEncGetEncodeProfileGUIDCount != NULL);
  return nvenc_api.nvEncGetEncodePresetCount (encoder, encodeGUID,
      encodePresetGUIDCount);
}

NVENCSTATUS
NvEncGetEncodePresetGUIDs (void *encoder, GUID encodeGUID,
    GUID * presetGUIDs, uint32_t guidArraySize, uint32_t * GUIDCount)
{
  g_assert (nvenc_api.nvEncGetEncodeProfileGUIDs != NULL);
  return nvenc_api.nvEncGetEncodePresetGUIDs (encoder, encodeGUID,
      presetGUIDs, guidArraySize, GUIDCount);
}

NVENCSTATUS
NvEncGetEncodePresetConfig (void *encoder, GUID encodeGUID,
    GUID presetGUID, NV_ENC_PRESET_CONFIG * presetConfig)
{
  g_assert (nvenc_api.nvEncGetEncodePresetConfig != NULL);
  return nvenc_api.nvEncGetEncodePresetConfig (encoder, encodeGUID, presetGUID,
      presetConfig);
}

NVENCSTATUS
NvEncGetEncodeCaps (void *encoder, GUID encodeGUID,
    NV_ENC_CAPS_PARAM * capsParam, int *capsVal)
{
  g_assert (nvenc_api.nvEncGetEncodeCaps != NULL);
  return nvenc_api.nvEncGetEncodeCaps (encoder, encodeGUID, capsParam, capsVal);
}

NVENCSTATUS
NvEncGetSequenceParams (void *encoder,
    NV_ENC_SEQUENCE_PARAM_PAYLOAD * sequenceParamPayload)
{
  g_assert (nvenc_api.nvEncGetSequenceParams != NULL);
  return nvenc_api.nvEncGetSequenceParams (encoder, sequenceParamPayload);
}

NVENCSTATUS
NvEncInitializeEncoder (void *encoder, NV_ENC_INITIALIZE_PARAMS * params)
{
  g_assert (nvenc_api.nvEncInitializeEncoder != NULL);
  return nvenc_api.nvEncInitializeEncoder (encoder, params);
}

NVENCSTATUS
NvEncReconfigureEncoder (void *encoder, NV_ENC_RECONFIGURE_PARAMS * params)
{
  g_assert (nvenc_api.nvEncReconfigureEncoder != NULL);
  return nvenc_api.nvEncReconfigureEncoder (encoder, params);
}

NVENCSTATUS
NvEncRegisterResource (void *encoder, NV_ENC_REGISTER_RESOURCE * params)
{
  g_assert (nvenc_api.nvEncRegisterResource != NULL);
  return nvenc_api.nvEncRegisterResource (encoder, params);
}

NVENCSTATUS
NvEncUnregisterResource (void *encoder, NV_ENC_REGISTERED_PTR resource)
{
  g_assert (nvenc_api.nvEncUnregisterResource != NULL);
  return nvenc_api.nvEncUnregisterResource (encoder, resource);
}

NVENCSTATUS
NvEncMapInputResource (void *encoder, NV_ENC_MAP_INPUT_RESOURCE * params)
{
  g_assert (nvenc_api.nvEncMapInputResource != NULL);
  return nvenc_api.nvEncMapInputResource (encoder, params);
}

NVENCSTATUS
NvEncUnmapInputResource (void *encoder, NV_ENC_INPUT_PTR input_buffer)
{
  g_assert (nvenc_api.nvEncUnmapInputResource != NULL);
  return nvenc_api.nvEncUnmapInputResource (encoder, input_buffer);
}

NVENCSTATUS
NvEncCreateInputBuffer (void *encoder, NV_ENC_CREATE_INPUT_BUFFER * input_buf)
{
  g_assert (nvenc_api.nvEncCreateInputBuffer != NULL);
  return nvenc_api.nvEncCreateInputBuffer (encoder, input_buf);
}

NVENCSTATUS
NvEncLockInputBuffer (void *encoder, NV_ENC_LOCK_INPUT_BUFFER * input_buf)
{
  g_assert (nvenc_api.nvEncLockInputBuffer != NULL);
  return nvenc_api.nvEncLockInputBuffer (encoder, input_buf);
}

NVENCSTATUS
NvEncUnlockInputBuffer (void *encoder, NV_ENC_INPUT_PTR input_buf)
{
  g_assert (nvenc_api.nvEncUnlockInputBuffer != NULL);
  return nvenc_api.nvEncUnlockInputBuffer (encoder, input_buf);
}

NVENCSTATUS
NvEncDestroyInputBuffer (void *encoder, NV_ENC_INPUT_PTR input_buf)
{
  g_assert (nvenc_api.nvEncDestroyInputBuffer != NULL);
  return nvenc_api.nvEncDestroyInputBuffer (encoder, input_buf);
}

NVENCSTATUS
NvEncCreateBitstreamBuffer (void *encoder, NV_ENC_CREATE_BITSTREAM_BUFFER * bb)
{
  g_assert (nvenc_api.nvEncCreateBitstreamBuffer != NULL);
  return nvenc_api.nvEncCreateBitstreamBuffer (encoder, bb);
}

NVENCSTATUS
NvEncLockBitstream (void *encoder, NV_ENC_LOCK_BITSTREAM * lock_bs)
{
  g_assert (nvenc_api.nvEncLockBitstream != NULL);
  return nvenc_api.nvEncLockBitstream (encoder, lock_bs);
}

NVENCSTATUS
NvEncUnlockBitstream (void *encoder, NV_ENC_OUTPUT_PTR bb)
{
  g_assert (nvenc_api.nvEncUnlockBitstream != NULL);
  return nvenc_api.nvEncUnlockBitstream (encoder, bb);
}

NVENCSTATUS
NvEncDestroyBitstreamBuffer (void *encoder, NV_ENC_OUTPUT_PTR bit_buf)
{
  g_assert (nvenc_api.nvEncDestroyBitstreamBuffer != NULL);
  return nvenc_api.nvEncDestroyBitstreamBuffer (encoder, bit_buf);
}

NVENCSTATUS
NvEncEncodePicture (void *encoder, NV_ENC_PIC_PARAMS * pic_params)
{
  g_assert (nvenc_api.nvEncEncodePicture != NULL);
  return nvenc_api.nvEncEncodePicture (encoder, pic_params);
}

gboolean
gst_nvenc_cmp_guid (GUID g1, GUID g2)
{
  return (g1.Data1 == g2.Data1 && g1.Data2 == g2.Data2 && g1.Data3 == g2.Data3
      && g1.Data4[0] == g2.Data4[0] && g1.Data4[1] == g2.Data4[1]
      && g1.Data4[2] == g2.Data4[2] && g1.Data4[3] == g2.Data4[3]
      && g1.Data4[4] == g2.Data4[4] && g1.Data4[5] == g2.Data4[5]
      && g1.Data4[6] == g2.Data4[6] && g1.Data4[7] == g2.Data4[7]);
}

NV_ENC_BUFFER_FORMAT
gst_nvenc_get_nv_buffer_format (GstVideoFormat fmt)
{
  switch (fmt) {
    case GST_VIDEO_FORMAT_NV12:
      return NV_ENC_BUFFER_FORMAT_NV12_PL;
    case GST_VIDEO_FORMAT_YV12:
      return NV_ENC_BUFFER_FORMAT_YV12_PL;
    case GST_VIDEO_FORMAT_I420:
      return NV_ENC_BUFFER_FORMAT_IYUV_PL;
    case GST_VIDEO_FORMAT_Y444:
      return NV_ENC_BUFFER_FORMAT_YUV444_PL;
    case GST_VIDEO_FORMAT_P010_10LE:
    case GST_VIDEO_FORMAT_P010_10BE:
      return NV_ENC_BUFFER_FORMAT_YUV420_10BIT;
    default:
      break;
  }
  return NV_ENC_BUFFER_FORMAT_UNDEFINED;
}

CUcontext
gst_nvenc_create_cuda_context (guint device_id)
{
  CUcontext cuda_ctx, old_ctx;
  CUresult cres = CUDA_SUCCESS;
  CUdevice cdev = 0, cuda_dev = -1;
  int dev_count = 0;
  char name[256];
  int min = 0, maj = 0;
  int i;

  GST_INFO ("Initialising CUDA..");

  cres = CuInit (0);

  if (cres != CUDA_SUCCESS) {
    GST_WARNING ("Failed to initialise CUDA, error code: 0x%08x", cres);
    return NULL;
  }

  GST_INFO ("Initialised CUDA");

  cres = CuDeviceGetCount (&dev_count);
  if (cres != CUDA_SUCCESS || dev_count == 0) {
    GST_WARNING ("No CUDA devices detected");
    return NULL;
  }

  GST_INFO ("%d CUDA device(s) detected", dev_count);
  for (i = 0; i < dev_count; ++i) {
    if (CuDeviceGet (&cdev, i) == CUDA_SUCCESS
        && CuDeviceGetName (name, sizeof (name), cdev) == CUDA_SUCCESS
        && CuDeviceGetAttribute (&maj,
            CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MAJOR, cdev) == CUDA_SUCCESS
        && CuDeviceGetAttribute (&min,
            CU_DEVICE_ATTRIBUTE_COMPUTE_CAPABILITY_MINOR,
            cdev) == CUDA_SUCCESS) {
      GST_INFO ("GPU #%d supports NVENC: %s (%s) (Compute SM %d.%d)", i,
          (((maj << 4) + min) >= 0x30) ? "yes" : "no", name, maj, min);
      if (i == device_id) {
        cuda_dev = cdev;
      }
    }
  }

  if (cuda_dev == -1) {
    GST_WARNING ("Device with id %d does not exist or does not support NVENC",
        device_id);
    return NULL;
  }

  if (CuCtxCreate (&cuda_ctx, 0, cuda_dev) != CUDA_SUCCESS) {
    GST_WARNING ("Failed to create CUDA context for cuda device %d", cuda_dev);
    return NULL;
  }

  if (CuCtxPopCurrent (&old_ctx) != CUDA_SUCCESS) {
    return NULL;
  }

  GST_INFO ("Created CUDA context %p", cuda_ctx);

  return cuda_ctx;
}

gboolean
gst_nvenc_destroy_cuda_context (CUcontext ctx)
{
  GST_INFO ("Destroying CUDA context %p", ctx);
  return (CuCtxDestroy (ctx) == CUDA_SUCCESS);
}

static gboolean
load_nvenc_library (void)
{
  GModule *module;

  module = g_module_open (NVENC_LIBRARY_NAME, G_MODULE_BIND_LAZY);
  if (module == NULL) {
    GST_WARNING ("Could not open library %s, %s",
        NVENC_LIBRARY_NAME, g_module_error ());
    return FALSE;
  }

  if (!g_module_symbol (module, "NvEncodeAPICreateInstance",
          (gpointer *) & nvEncodeAPICreateInstance)) {
    GST_ERROR ("%s", g_module_error ());
    return FALSE;
  }

  return TRUE;
}

typedef struct
{
  GstVideoFormat gst_format;
  NV_ENC_BUFFER_FORMAT nv_format;
  gboolean is_10bit;

  gboolean supported;
} GstNvEncFormat;

gboolean
gst_nv_enc_get_supported_input_formats (gpointer encoder, GUID codec_id,
    GValue ** formats)
{
  guint32 i, count = 0;
  NV_ENC_BUFFER_FORMAT format_list[64];
  GValue val = G_VALUE_INIT;
  GValue *ret = NULL;
  NV_ENC_CAPS_PARAM param = { 0, };
  gint support_yuv444 = 0;
  gint support_10bit = 0;
  guint num_format = 0;
  GstNvEncFormat format_map[] = {
    {GST_VIDEO_FORMAT_NV12, NV_ENC_BUFFER_FORMAT_NV12, FALSE, FALSE},
    {GST_VIDEO_FORMAT_YV12, NV_ENC_BUFFER_FORMAT_YV12, FALSE, FALSE},
    {GST_VIDEO_FORMAT_I420, NV_ENC_BUFFER_FORMAT_IYUV, FALSE, FALSE},
    {GST_VIDEO_FORMAT_Y444, NV_ENC_BUFFER_FORMAT_YUV444, FALSE, FALSE},
#if G_BYTE_ORDER == G_LITTLE_ENDIAN
    {GST_VIDEO_FORMAT_P010_10LE, NV_ENC_BUFFER_FORMAT_YUV420_10BIT, TRUE,
        FALSE},
#else
    {GST_VIDEO_FORMAT_P010_10BE, NV_ENC_BUFFER_FORMAT_YUV420_10BIT, TRUE,
        FALSE},
#endif
  };

  param.version = NV_ENC_CAPS_PARAM_VER;
  param.capsToQuery = NV_ENC_CAPS_SUPPORT_YUV444_ENCODE;
  if (NvEncGetEncodeCaps (encoder,
          codec_id, &param, &support_yuv444) != NV_ENC_SUCCESS) {
    support_yuv444 = 0;
  }

  param.capsToQuery = NV_ENC_CAPS_SUPPORT_10BIT_ENCODE;
  if (NvEncGetEncodeCaps (encoder,
          codec_id, &param, &support_10bit) != NV_ENC_SUCCESS) {
    support_10bit = 0;
  }

  if (NvEncGetInputFormats (encoder,
          codec_id, format_list, G_N_ELEMENTS (format_list),
          &count) != NV_ENC_SUCCESS || count == 0) {
    return FALSE;
  }

  for (i = 0; i < count; i++) {
    GST_INFO ("input format: 0x%08x", format_list[i]);
    switch (format_list[i]) {
      case NV_ENC_BUFFER_FORMAT_NV12:
        if (!format_map[0].supported) {
          format_map[0].supported = TRUE;
          num_format++;
        }
        break;
      case NV_ENC_BUFFER_FORMAT_YV12:
        if (!format_map[1].supported) {
          format_map[0].supported = TRUE;
          num_format++;
        }
        break;
      case NV_ENC_BUFFER_FORMAT_IYUV:
        if (!format_map[2].supported) {
          format_map[2].supported = TRUE;
          num_format++;
        }
        break;
      case NV_ENC_BUFFER_FORMAT_YUV444:
        if (support_yuv444 && !format_map[3].supported) {
          format_map[3].supported = TRUE;
          num_format++;
        }
        break;
      case NV_ENC_BUFFER_FORMAT_YUV420_10BIT:
        if (support_yuv444 && support_10bit && !format_map[4].supported) {
          format_map[4].supported = TRUE;
          num_format++;
        }
        break;
      default:
        GST_FIXME ("unmapped input format: 0x%08x", format_list[i]);
        break;
    }
  }

  if (num_format == 0)
    return FALSE;

  /* process a second time so we can add formats in the order we want */
  g_value_init (&val, G_TYPE_STRING);
  ret = g_new0 (GValue, 1);
  g_value_init (ret, GST_TYPE_LIST);

  for (i = 0; i < G_N_ELEMENTS (format_map); i++) {
    if (!format_map[i].supported)
      continue;

    g_value_set_static_string (&val,
        gst_video_format_to_string (format_map[i].gst_format));

    gst_value_list_append_value (ret, &val);
  }

  g_value_unset (&val);

  *formats = ret;

  return TRUE;
}

GValue *
gst_nv_enc_get_interlace_modes (gpointer enc, GUID codec_id)
{
  NV_ENC_CAPS_PARAM caps_param = { 0, };
  GValue *list;
  GValue val = G_VALUE_INIT;
  gint interlace_modes = 0;

  caps_param.version = NV_ENC_CAPS_PARAM_VER;
  caps_param.capsToQuery = NV_ENC_CAPS_SUPPORT_FIELD_ENCODING;

  if (NvEncGetEncodeCaps (enc, codec_id, &caps_param,
          &interlace_modes) != NV_ENC_SUCCESS)
    interlace_modes = 0;

  list = g_new0 (GValue, 1);

  g_value_init (list, GST_TYPE_LIST);
  g_value_init (&val, G_TYPE_STRING);

  g_value_set_static_string (&val, "progressive");
  gst_value_list_append_value (list, &val);

  if (interlace_modes == 0)
    return list;

  if (interlace_modes >= 1) {
    g_value_set_static_string (&val, "interleaved");
    gst_value_list_append_value (list, &val);
    g_value_set_static_string (&val, "mixed");
    gst_value_list_append_value (list, &val);
    g_value_unset (&val);
  }
  /* TODO: figure out what nvenc frame based interlacing means in gst terms */

  return list;
}

typedef struct
{
  const gchar *gst_profile;
  const GUID nv_profile;
  const GUID codec_id;
  const gboolean need_yuv444;
  const gboolean need_10bit;

  gboolean supported;
} GstNvEncCodecProfile;

GValue *
gst_nv_enc_get_supported_codec_profiles (gpointer enc, GUID codec_id)
{
  NVENCSTATUS nv_ret;
  GUID profile_guids[64];
  GValue *ret;
  GValue val = G_VALUE_INIT;
  guint i, j, n, n_profiles;
  NV_ENC_CAPS_PARAM param = { 0, };
  gint support_yuv444 = 0;
  gint support_10bit = 0;
  GstNvEncCodecProfile profiles[] = {
    /* avc profiles */
    {"baseline", NV_ENC_H264_PROFILE_BASELINE_GUID, NV_ENC_CODEC_H264_GUID,
        FALSE, FALSE, FALSE},
    {"main", NV_ENC_H264_PROFILE_MAIN_GUID, NV_ENC_CODEC_H264_GUID, FALSE,
        FALSE, FALSE},
    {"high", NV_ENC_H264_PROFILE_HIGH_GUID, NV_ENC_CODEC_H264_GUID, FALSE,
        FALSE, FALSE},
    {"high-4:4:4", NV_ENC_H264_PROFILE_HIGH_444_GUID, NV_ENC_CODEC_H264_GUID,
        TRUE, FALSE, FALSE},
    /* hevc profiles */
    {"main", NV_ENC_HEVC_PROFILE_MAIN_GUID, NV_ENC_CODEC_HEVC_GUID, FALSE,
        FALSE, FALSE},
    {"main-10", NV_ENC_HEVC_PROFILE_MAIN10_GUID, NV_ENC_CODEC_HEVC_GUID, FALSE,
        TRUE, FALSE},
    {"main-444", NV_ENC_HEVC_PROFILE_FREXT_GUID, NV_ENC_CODEC_HEVC_GUID, TRUE,
        FALSE, FALSE},
#if 0
    /* FIXME: seems to unsupported format */
    {"main-444-10", NV_ENC_HEVC_PROFILE_FREXT_GUID, FALSE}
#endif
  };

  param.version = NV_ENC_CAPS_PARAM_VER;
  param.capsToQuery = NV_ENC_CAPS_SUPPORT_YUV444_ENCODE;
  if (NvEncGetEncodeCaps (enc,
          codec_id, &param, &support_yuv444) != NV_ENC_SUCCESS) {
    support_yuv444 = 0;
  }

  param.capsToQuery = NV_ENC_CAPS_SUPPORT_10BIT_ENCODE;
  if (NvEncGetEncodeCaps (enc,
          codec_id, &param, &support_10bit) != NV_ENC_SUCCESS) {
    support_10bit = 0;
  }

  nv_ret = NvEncGetEncodeProfileGUIDCount (enc, codec_id, &n);

  if (nv_ret != NV_ENC_SUCCESS)
    return NULL;

  nv_ret = NvEncGetEncodeProfileGUIDs (enc,
      codec_id, profile_guids, G_N_ELEMENTS (profile_guids), &n);

  if (nv_ret != NV_ENC_SUCCESS)
    return NULL;

  n_profiles = 0;

  for (i = 0; i < n; i++) {
    for (j = 0; j < G_N_ELEMENTS (profiles); j++) {
      if (profiles[j].supported == FALSE &&
          gst_nvenc_cmp_guid (profile_guids[i], profiles[j].nv_profile) &&
          gst_nvenc_cmp_guid (codec_id, profiles[j].codec_id)) {
        if (profiles[j].need_yuv444 && !support_yuv444)
          continue;

        if (profiles[j].need_10bit && !support_10bit)
          continue;

        profiles[j].supported = TRUE;
        n_profiles++;
      }
    }
  }

  if (n_profiles == 0)
    return NULL;

  ret = g_new0 (GValue, 1);

  g_value_init (ret, GST_TYPE_LIST);
  g_value_init (&val, G_TYPE_STRING);

  for (i = 0; i < G_N_ELEMENTS (profiles); i++) {
    if (!profiles[i].supported)
      continue;

    g_value_set_static_string (&val, profiles[i].gst_profile);
    gst_value_list_append_value (ret, &val);
  }

  g_value_unset (&val);

  return ret;
}

static void
gst_nv_enc_register (GstPlugin * plugin, GType type, GUID codec_id,
    const gchar * codec, guint rank, gint device_count)
{
  gint i;

  for (i = 0; i < device_count; i++) {
    CUdevice cuda_device;
    CUcontext cuda_ctx, dummy;
    GValue *formats = NULL;
    GValue *profiles;
    GValue *interlace_modes;
    gpointer enc;
    NV_ENC_OPEN_ENCODE_SESSION_EX_PARAMS params = { 0, };
    NV_ENC_CAPS_PARAM caps_param = { 0, };
    GUID guids[16];
    guint32 count;
    gint max_width = 0;
    gint max_height = 0;
    GstCaps *sink_templ = NULL;
    GstCaps *src_templ = NULL;
    gchar *name;
    gint j;

    if (CuDeviceGet (&cuda_device, i) != CUDA_SUCCESS)
      continue;

    if (CuCtxCreate (&cuda_ctx, 0, cuda_device) != CUDA_SUCCESS)
      continue;

    if (CuCtxPopCurrent (&dummy) != CUDA_SUCCESS) {
      goto cuda_free;
    }

    params.version = NV_ENC_OPEN_ENCODE_SESSION_EX_PARAMS_VER;
    params.apiVersion = NVENCAPI_VERSION;
    params.device = cuda_ctx;
    params.deviceType = NV_ENC_DEVICE_TYPE_CUDA;

    if (NvEncOpenEncodeSessionEx (&params, &enc) != NV_ENC_SUCCESS) {
      goto cuda_free;
    }

    if (NvEncGetEncodeGUIDs (enc, guids, G_N_ELEMENTS (guids),
            &count) != NV_ENC_SUCCESS) {
      goto enc_free;
    }

    for (j = 0; j < count; j++) {
      if (gst_nvenc_cmp_guid (guids[j], codec_id))
        break;
    }

    if (j == count)
      goto enc_free;

    if (!gst_nv_enc_get_supported_input_formats (enc, codec_id, &formats))
      goto enc_free;

    profiles = gst_nv_enc_get_supported_codec_profiles (enc, codec_id);
    if (!profiles)
      goto free_format;

    caps_param.version = NV_ENC_CAPS_PARAM_VER;
    caps_param.capsToQuery = NV_ENC_CAPS_WIDTH_MAX;
    if (NvEncGetEncodeCaps (enc,
            codec_id, &caps_param, &max_width) != NV_ENC_SUCCESS) {
      GST_WARNING ("could not query max width");
      max_width = 4096;
    } else if (max_width < 4096) {
      GST_WARNING ("max width %d is less than expected value", max_width);
      max_width = 4096;
    }

    caps_param.capsToQuery = NV_ENC_CAPS_HEIGHT_MAX;
    if (NvEncGetEncodeCaps (enc,
            codec_id, &caps_param, &max_height) != NV_ENC_SUCCESS) {
      GST_WARNING ("could not query max height");
      max_height = 4096;
    } else if (max_height < 4096) {
      GST_WARNING ("max height %d is less than expected value", max_height);
      max_height = 4096;
    }

    interlace_modes = gst_nv_enc_get_interlace_modes (enc, codec_id);

    sink_templ = gst_caps_new_empty_simple ("video/x-raw");
    gst_caps_set_value (sink_templ, "format", formats);

    gst_caps_set_simple (sink_templ,
        "width", GST_TYPE_INT_RANGE, 16, max_width,
        "height", GST_TYPE_INT_RANGE, 16, max_height,
        "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1, NULL);

    if (interlace_modes) {
      gst_caps_set_value (sink_templ, "interlace-mode", interlace_modes);
      g_value_unset (interlace_modes);
      g_free (interlace_modes);
    }
#if HAVE_NVCODEC_GST_GL
    {
      GstCaps *gl_caps = gst_caps_copy (sink_templ);
      gst_caps_set_features_simple (gl_caps,
          gst_caps_features_from_string (GST_CAPS_FEATURE_MEMORY_GL_MEMORY));
      gst_caps_append (sink_templ, gl_caps);
    }
#endif

    name = g_strdup_printf ("video/x-%s", codec);
    src_templ = gst_caps_new_simple (name,
        "width", GST_TYPE_INT_RANGE, 16, max_width,
        "height", GST_TYPE_INT_RANGE, 16, max_height,
        "framerate", GST_TYPE_FRACTION_RANGE, 0, 1, G_MAXINT, 1,
        "stream-format", G_TYPE_STRING, "byte-stream",
        "alignment", G_TYPE_STRING, "au", NULL);
    gst_caps_set_value (src_templ, "profile", profiles);
    g_free (name);

    GST_DEBUG ("sink template caps %" GST_PTR_FORMAT, sink_templ);
    GST_DEBUG ("src template caps %" GST_PTR_FORMAT, src_templ);

    g_value_unset (profiles);
    g_free (profiles);

  free_format:
    if (formats) {
      g_value_unset (formats);
      g_free (formats);
    }
    /* fall-through */

  enc_free:
    NvEncDestroyEncoder (enc);
    /* fall-through */

  cuda_free:
    CuCtxDestroy (cuda_ctx);

    if (sink_templ && src_templ)
      gst_nv_base_enc_register (plugin, type, codec, i, rank, sink_templ,
          src_templ);

    gst_clear_caps (&sink_templ);
    gst_clear_caps (&src_templ);
  }
}


void
gst_nvenc_plugin_init (GstPlugin * plugin)
{
  GST_DEBUG_CATEGORY_INIT (gst_nvenc_debug, "nvenc", 0, "Nvidia NVENC encoder");

  nvenc_api.version = NV_ENCODE_API_FUNCTION_LIST_VER;
  if (!load_nvenc_library ()) {
    GST_INFO ("Failed to load nvenc library");
    return;
  }

  if (nvEncodeAPICreateInstance (&nvenc_api) != NV_ENC_SUCCESS) {
    GST_ERROR ("Failed to get NVEncodeAPI function table!");
  } else {
    CUresult cuda_ret;
    gint dev_count = 0;

    GST_INFO ("Created NVEncodeAPI instance, got function table");

    cuda_ret = CuInit (0);
    if (cuda_ret != CUDA_SUCCESS) {
      GST_ERROR ("Failed to initialize CUDA API");
      return;
    }

    cuda_ret = CuDeviceGetCount (&dev_count);
    if (cuda_ret != CUDA_SUCCESS || dev_count == 0) {
      GST_ERROR ("No CUDA devices detected");
      return;
    }

    gst_nv_enc_register (plugin, GST_TYPE_NV_H264_ENC,
        NV_ENC_CODEC_H264_GUID, "h264", GST_RANK_PRIMARY * 2, dev_count);
    gst_nv_enc_register (plugin, GST_TYPE_NV_H265_ENC,
        NV_ENC_CODEC_HEVC_GUID, "h265", GST_RANK_PRIMARY * 2, dev_count);

  }
}