diff options
Diffstat (limited to 'src/lib/openjp2/openjpeg.h')
| -rw-r--r-- | src/lib/openjp2/openjpeg.h | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/lib/openjp2/openjpeg.h b/src/lib/openjp2/openjpeg.h index 79e0bb4f..f36286eb 100644 --- a/src/lib/openjp2/openjpeg.h +++ b/src/lib/openjp2/openjpeg.h @@ -1336,6 +1336,37 @@ OPJ_API OPJ_BOOL OPJ_CALLCONV opj_read_header(opj_stream_t *p_stream, opj_codec_t *p_codec, opj_image_t **p_image); + +/** Restrict the number of components to decode. + * + * This function should be called after opj_read_header(). + * + * This function enables to restrict the set of decoded components to the + * specified indices. + * Note that the current implementation (apply_color_transforms == OPJ_FALSE) + * is such that neither the multi-component transform at codestream level, + * nor JP2 channel transformations will be applied. + * Consequently the indices are relative to the codestream. + * + * Note: opj_decode_tile_data() should not be used together with opj_set_decoded_components(). + * + * @param p_codec the jpeg2000 codec to read. + * @param numcomps Size of the comps_indices array. + * @param comps_indices Array of numcomps values representing the indices + * of the components to decode (relative to the + * codestream, starting at 0) + * @param apply_color_transforms Whether multi-component transform at codestream level + * or JP2 channel transformations should be applied. + * Currently this parameter should be set to OPJ_FALSE. + * Setting it to OPJ_TRUE will result in an error. + * + * @return OPJ_TRUE in case of success. + */ +OPJ_API OPJ_BOOL OPJ_CALLCONV opj_set_decoded_components(opj_codec_t *p_codec, + OPJ_UINT32 numcomps, + const OPJ_UINT32* comps_indices, + OPJ_BOOL apply_color_transforms); + /** * Sets the given area to be decoded. This function should be called right after opj_read_header and before any tile header reading. * @@ -1452,6 +1483,8 @@ OPJ_API OPJ_BOOL OPJ_CALLCONV opj_read_tile_header(opj_codec_t *p_codec, * Reads a tile data. This function is compulsory and allows one to decode tile data. opj_read_tile_header should be called before. * The user may need to refer to the image got by opj_read_header to understand the size being taken by the tile. * + * Note: opj_decode_tile_data() should not be used together with opj_set_decoded_components(). + * * @param p_codec the jpeg2000 codec. * @param p_tile_index the index of the tile being decoded, this should be the value set by opj_read_tile_header. * @param p_data pointer to a memory block that will hold the decoded data. |