.. _nvjpeg2kdecode-label:

nvjpeg2kDecode()
*****************

Decodes a single image, and writes it to the output device buffers. The function is asynchronous with respect to the host.
All GPU tasks will be submitted to the provided :code:`stream`. Prior to calling this function user must parse the bitstream
using :ref:`nvjpeg2kstreamparse-label` such that the bitstream information is stored in :code:`jpeg2k_stream`.

**Signature:**

.. code-block:: cpp

    nvjpeg2kStatus_t nvjpeg2kDecode(nvjpeg2kHandle_t handle, 
            nvjpeg2kDecodeState_t decode_state, 
            nvjpeg2kStream_t jpeg2k_stream, 
            nvjpeg2kImage_t* decode_output,
            cudaStream_t stream);

**Parameters:**

.. list-table::
  :header-rows: 1
  :widths: 15 10 10 20

  * - Parameter
    - Input/Output
    - Memory
    - Description
  * - nvjpeg2kHandle_t handle
    - Input
    - Host
    - library handle
  * - nvjpeg2kDecodeState_t decode_state
    - Input
    - Host
    - decode state handle
  * - nvjpeg2kStream_t jpeg2k_stream
    - Input
    - Host
    - nvjpeg2k bitstream handle
  * - nvjpeg2kImage_t* decode_output
    - Input/Output
    - Host
    - Decode output struct. The struct should be on host memory.
      The image component pointers should point to device memory. See :ref:`nvjpeg2kimagedata-label`
  * - cudaStream_t stream
    - Input
    - Host
    - Instance of cudaStream_t. Can be set to 0.

**Returns:**

:code:`nvjpeg2kStatus_t` - An error code as specified in :ref:`nvjpeg2kapireturncodes-label`

.. _nvjpeg2kdecodetile-label:

nvjpeg2kDecodeTile()
*********************
Decodes a tile within an image and writes it to the output device buffers. The function is asynchronous with respect to the host.
All GPU tasks will be submitted to the provided :code:`stream`. Prior to calling this function user must parse the bitstream
using :ref:`nvjpeg2kstreamparse-label` such that the bitstream information is stored in :code:`jpeg2k_stream`.



**Signature:**

.. code-block:: cpp

    nvjpeg2kStatus_t nvjpeg2kDecodeTile(nvjpeg2kHandle_t handle, 
            nvjpeg2kDecodeState_t decode_state, 
            nvjpeg2kStream_t jpeg2k_stream, 
            nvjpeg2kDecodeParams_t decode_params,
            uint32_t tile_id,
            uint32_t num_res_levels,
            nvjpeg2kImage_t* decode_output,
            cudaStream_t stream);

**Parameters:**

.. list-table::
  :header-rows: 1
  :widths: 15 10 10 20

  * - Parameter
    - Input/Output
    - Memory
    - Description
  * - nvjpeg2kHandle_t handle
    - Input
    - Host
    - library handle
  * - nvjpeg2kDecodeState_t decode_state
    - Input
    - Host
    - decode state handle
  * - nvjpeg2kStream_t jpeg2k_stream
    - Input
    - Host
    - nvjpeg2k bitstream handle
  * - nvjpeg2kDecodeParams_t decode_params
    - Input
    - Host
    - Used to control the decoded output (like specifying an area of interest) Can be set to NULL.
  * - uint32_t tile_id
    - Input
    - Host
    - Raster scan based tile index
  * - uint32_t num_res_levels
    - Input
    - Host
    - Number of Resolutions to be decoded within a tile, 
      When set 0, image is decoded at full resolution
      Maximum allowed resolutions in a tile can be determined using :ref:`nvjpeg2kstreamgetresolutionsintile-label`
  * - nvjpeg2kImage_t* decode_output
    - Input/Output
    - Host
    - Decode output struct. The struct should be on host memory.
      The image component pointers should point to device memory. See :ref:`nvjpeg2kimagedata-label`
  * - cudaStream_t stream
    - Input
    - Host
    - Instance of cudaStream_t. Can be set to 0.

**Returns:**

:code:`nvjpeg2kStatus_t` - An error code as specified in :ref:`nvjpeg2kapireturncodes-label`