C++ LLImageJ2C::updateRawDiscardLevel方法代码示例

BOOL LLImageJ2CKDU::initDecode(LLImageJ2C &base, LLImageRaw &raw_image, F32 decode_time, ECodeStreamMode mode, S32 first_channel, S32 max_channel_count, int discard_level, int* region)
{
	base.resetLastError();

	// *FIX: kdu calls our callback function if there's an error, and then bombs.
	// To regain control, we throw an exception, and catch it here.
	try
	{
		// Merov : Test!! DO NOT COMMIT!!
		//findDiscardLevelsBoundaries(base);

		base.updateRawDiscardLevel();
		setupCodeStream(base, TRUE, mode);

		mRawImagep = &raw_image;
		mCodeStreamp->change_appearance(false, true, false);

		// Apply loading discard level and cropping if required
		kdu_dims* region_kdu = NULL;
		if (region != NULL)
		{
			region_kdu = new kdu_dims;
			region_kdu->pos.x  = region[0];
			region_kdu->pos.y  = region[1];
			region_kdu->size.x = region[2] - region[0];
			region_kdu->size.y = region[3] - region[1];
		}
		int discard = (discard_level != -1 ? discard_level : base.getRawDiscardLevel());
		//llinfos << "Merov debug : initDecode, discard used = " << discard << ", asked = " << discard_level << llendl;
		// Apply loading restrictions
		mCodeStreamp->apply_input_restrictions( first_channel, max_channel_count, discard, 0, region_kdu);
		
		// Clean-up
		if (region_kdu)
		{
			delete region_kdu;
			region_kdu = NULL;
		}

		// Resize raw_image according to the image to be decoded
		kdu_dims dims; mCodeStreamp->get_dims(0,dims);
		S32 channels = base.getComponents() - first_channel;
		channels = llmin(channels,max_channel_count);
		raw_image.resize(dims.size.x, dims.size.y, channels);

		if (!mTileIndicesp)
		{
			mTileIndicesp = new kdu_dims;
		}
		mCodeStreamp->get_valid_tiles(*mTileIndicesp);
		if (!mTPosp)
		{
			mTPosp = new kdu_coords;
			mTPosp->y = 0;
			mTPosp->x = 0;
		}
	}
	catch (const char* msg)
	{
		base.setLastError(ll_safe_string(msg));
		return FALSE;
	}
	catch (...)
	{
		base.setLastError("Unknown J2C error");
		return FALSE;
	}

	return TRUE;
}

BOOL LLImageJ2COJ::getMetadata(LLImageJ2C &base)
{
	//
	// FIXME: We get metadata by decoding the ENTIRE image.
	//

	// Update the raw discard level
	base.updateRawDiscardLevel();

	opj_dparameters_t parameters;	/* decompression parameters */
	opj_event_mgr_t event_mgr;		/* event manager */
	opj_image_t *image = NULL;

	opj_dinfo_t* dinfo = NULL;	/* handle to a decompressor */
	opj_cio_t *cio = NULL;


	/* configure the event callbacks (not required) */
	memset(&event_mgr, 0, sizeof(opj_event_mgr_t));
	event_mgr.error_handler = error_callback;
	event_mgr.warning_handler = warning_callback;
	event_mgr.info_handler = info_callback;

	/* set decoding parameters to default values */
	opj_set_default_decoder_parameters(&parameters);

	// Only decode what's required to get the size data.
	parameters.cp_limit_decoding=LIMIT_TO_MAIN_HEADER;

	//parameters.cp_reduce = mRawDiscardLevel;

	/* decode the code-stream */
	/* ---------------------- */

	/* JPEG-2000 codestream */

	/* get a decoder handle */
	dinfo = opj_create_decompress(CODEC_J2K);

	/* catch events using our callbacks and give a local context */
	opj_set_event_mgr((opj_common_ptr)dinfo, &event_mgr, stderr);			

	/* setup the decoder decoding parameters using user parameters */
	opj_setup_decoder(dinfo, &parameters);

	/* open a byte stream */
	cio = opj_cio_open((opj_common_ptr)dinfo, base.getData(), base.getDataSize());

	/* decode the stream and fill the image structure */
	image = opj_decode(dinfo, cio);

	/* close the byte stream */
	opj_cio_close(cio);

	/* free remaining structures */
	if(dinfo)
	{
		opj_destroy_decompress(dinfo);
	}

	if(!image)
	{
		llwarns << "ERROR -> getMetadata: failed to decode image!" << llendl;
		return FALSE;
	}

	// Copy image data into our raw image format (instead of the separate channel format
	S32 width = 0;
	S32 height = 0;

	S32 img_components = image->numcomps;
	width = image->x1 - image->x0;
	height = image->y1 - image->y0;
	base.setSize(width, height, img_components);

	/* free image data structure */
	opj_image_destroy(image);
	return TRUE;
}