nvtiffDecode()¶

Decodes image data on the GPU which is specified in tiff_stream. Each image in the TIFF file is copied into the respective buffer pointed to by “imageOut_d”. This function is fully asynchronous.

When the photometric interpretation of an image is NVTIFF_PHOTOMETRIC_PALETTE or NVTIFF_PHOTOMETRIC_YCBCR, the decode output will be converted to RGB.

For images with multiple samples, the decode output will always be in planar contiguous format.

Signature:

nvtiffStatus_t nvtiffDecode(nvtiffStream_t tiff_stream,
                    nvtiffDecoder_t nvtiff_decoder,
                    unsigned char **image_out,
                    cudaStream_t cuda_stream);

Parameters:

Parameter	Input/Output	Memory	Description
nvtiffStream_t tiff_stream	Input	Host	`tiff_stream` handle in which the TIFF file has been read.
nvtiffDecoder_t nvtiff_decoder	Input	Host	Decoder handle
unsigned char **imageOut_d	Output	Host	Host array (of size num_images in the TIFF file) of pointers to device buffers.Each device buffer should have a size of image_width * image height * bitdepth * samples_per_pixel When the photometric interpretation for an image is palette mode, the device buffer should have a size of image_width * image height * 3 * 2
cudaStream_t cuda_stream	Input	Host	`cuda_stream` where all the GPU work will be submitted

Returns:

nvtiffStatus_t - An error code as specified in Decode API Return Status Codes

nvtiffDecodeRange()¶

This function is similar to nvtiffDecode(). It allows the user to specify a range of images to be decoded (instead of decoding all images in the file).

When the photometric interpretation of an image is NVTIFF_PHOTOMETRIC_PALETTE or NVTIFF_PHOTOMETRIC_YCBCR, the decode output will be converted to RGB.

For images with multiple samples, the decode output will always be in planar contiguous format.

Signature:

nvtiffStatus_t NVTIFFAPI nvtiffDecodeRange(nvtiffStream_t tiff_stream,
                nvtiffDecoder_t decoder,
                unsigned int sub_file_start,
                unsigned int sub_file_num,
                unsigned char **image_out,
                cudaStream_t cuda_stream);

Parameters:

Parameter	Input/Output	Memory	Description
nvtiffStream_t tiff_stream	Input	Host	`tiff_stream` handle in which the TIFF file has been read.
nvtiffDecoder_t nvtiff_decoder	Input	Host	Decoder handle
unsigned int sub_file_start	Input	Host	Index of the first image to decode, in [0, tiff_info.num_sub_files).
unsigned int sub_file_num	Input	Host	Number of images to decode starting from `sub_file_start`, in (0, tiff_info.num_sub_files]
unsigned char **imageOut_d	Output	Host	Host array (of size num_images in the TIFF file) of pointers to device buffers.Each device buffer should have a size of image_width * image height * bitdepth * samples_per_pixel When the photometric interpretation for an image is palette mode, the device buffer should have a size of image_width * image height * 3 * 2
cudaStream_t cuda_stream	Input	Host	`cuda_stream` where all the GPU work will be submitted

Returns:

nvtiffStatus_t - An error code as specified in Decode API Return Status Codes

nvtiffDecodeImage()¶

Decodes a single image on the GPU which is specified in tiff_stream. The function is asynchronous with respect to the host. Additional control of the decode output is possible using an instance nvtiffDecodeParams_t.

Signature:

nvtiffStatus_t nvtiffDecodeImage(nvtiffStream_t tiff_stream,
      nvtiffDecoder_t decoder,
      nvtiffDecodeParams_t params,
      uint32_t image_id,
      void* image_out_d,
      cudaStream_t cuda_stream);

Parameters:

Parameter	Input/Output	Memory	Description
nvtiffStream_t tiff_stream	Input	Host	`tiff_stream` handle in which the TIFF file has been read.
nvtiffDecoder_t nvtiff_decoder	Input	Host	Decoder handle
nvtiffDecodeParams_t params	Input	Host	Used to control the decoded output (like specifying ROI, output format).
uint32_t image_id	Input	Host	Corresponds to the image index(IFDs) within a multi images TIFF file. Cannot exceed the total number of images in a TIFF file.
void* image_out_d	Output	Device	Decode output buffer. For allocation size, see nvtiffDecodeParamsSetOutputFormat()
cudaStream_t cuda_stream	Input	Host	`cuda_stream` where all the GPU work will be submitted

Returns:

nvtiffStatus_t - An error code as specified in Decode API Return Status Codes

nvtiffDecodeCheckSupported()¶

Helps determine whether any given image within a tiff file specified by tiff_stream can be decoded by nvTIFF. Returns NVTIFF_STATUS_SUCCESS, if the image is supported

Signature:

nvtiffStatus_t nvtiffDecodeCheckSupported(nvtiffStream_t tiff_stream,
      nvtiffDecoder_t decoder,
      nvtiffDecodeParams_t params,
      uint32_t image_id);

Parameters:

Parameter	Input/Output	Memory	Description
nvtiffStream_t tiff_stream	Input	Host	`tiff_stream` handle in which the TIFF file has been read.
nvtiffDecoder_t nvtiff_decoder	Input	Host	Decoder handle
nvtiffDecodeParams_t params	Input	Host	Used to control the decoded output (like specifying ROI, output format).
uint32_t image_id	Input	Host	Corresponds to the image index(IFDs) within a multi images TIFF file. Cannot exceed the total number of images in a TIFF file.

Returns:

nvtiffStatus_t - An error code as specified in Decode API Return Status Codes