view release on metacpan or  search on metacpan

src/Source/LibTIFF4/tif_write.c  view on Meta::CPAN

		strip = sample*td->td_stripsperimage + row/td->td_rowsperstrip;
	} else
		strip = row / td->td_rowsperstrip;
	/*
	 * Check strip array to make sure there's space. We don't support
	 * dynamically growing files that have data organized in separate
	 * bitplanes because it's too painful.  In that case we require that
	 * the imagelength be set properly before the first write (so that the
	 * strips array will be fully allocated above).
	 */
	if (strip >= td->td_nstrips && !TIFFGrowStrips(tif, 1, module))
		return (-1);
	if (strip != tif->tif_curstrip) {
		/*
		 * Changing strips -- flush any data present.
		 */
		if (!TIFFFlushData(tif))
			return (-1);
		tif->tif_curstrip = strip;
		/*
		 * Watch out for a growing image.  The value of strips/image
		 * will initially be 1 (since it can't be deduced until the
		 * imagelength is known).
		 */
		if (strip >= td->td_stripsperimage && imagegrew)
			td->td_stripsperimage =
			    TIFFhowmany_32(td->td_imagelength,td->td_rowsperstrip);
		tif->tif_row =
		    (strip % td->td_stripsperimage) * td->td_rowsperstrip;
		if ((tif->tif_flags & TIFF_CODERSETUP) == 0) {
			if (!(*tif->tif_setupencode)(tif))
				return (-1);
			tif->tif_flags |= TIFF_CODERSETUP;
		}
        
		tif->tif_rawcc = 0;
		tif->tif_rawcp = tif->tif_rawdata;

		if( td->td_stripbytecount[strip] > 0 )
		{
			/* if we are writing over existing tiles, zero length */
			td->td_stripbytecount[strip] = 0;

			/* this forces TIFFAppendToStrip() to do a seek */
			tif->tif_curoff = 0;
		}

		if (!(*tif->tif_preencode)(tif, sample))
			return (-1);
		tif->tif_flags |= TIFF_POSTENCODE;
	}
	/*
	 * Ensure the write is either sequential or at the
	 * beginning of a strip (or that we can randomly
	 * access the data -- i.e. no encoding).
	 */
	if (row != tif->tif_row) {
		if (row < tif->tif_row) {
			/*
			 * Moving backwards within the same strip:
			 * backup to the start and then decode
			 * forward (below).
			 */
			tif->tif_row = (strip % td->td_stripsperimage) *
			    td->td_rowsperstrip;
			tif->tif_rawcp = tif->tif_rawdata;
		}
		/*
		 * Seek forward to the desired row.
		 */
		if (!(*tif->tif_seek)(tif, row - tif->tif_row))
			return (-1);
		tif->tif_row = row;
	}

	/* swab if needed - note that source buffer will be altered */
	tif->tif_postdecode( tif, (uint8*) buf, tif->tif_scanlinesize );

	status = (*tif->tif_encoderow)(tif, (uint8*) buf,
	    tif->tif_scanlinesize, sample);

        /* we are now poised at the beginning of the next row */
	tif->tif_row = row + 1;
	return (status);
}

/*
 * Encode the supplied data and write it to the
 * specified strip.
 *
 * NB: Image length must be setup before writing.
 */
tmsize_t
TIFFWriteEncodedStrip(TIFF* tif, uint32 strip, void* data, tmsize_t cc)
{
	static const char module[] = "TIFFWriteEncodedStrip";
	TIFFDirectory *td = &tif->tif_dir;
	uint16 sample;

	if (!WRITECHECKSTRIPS(tif, module))
		return ((tmsize_t) -1);
	/*
	 * Check strip array to make sure there's space.
	 * We don't support dynamically growing files that
	 * have data organized in separate bitplanes because
	 * it's too painful.  In that case we require that
	 * the imagelength be set properly before the first
	 * write (so that the strips array will be fully
	 * allocated above).
	 */
	if (strip >= td->td_nstrips) {
		if (td->td_planarconfig == PLANARCONFIG_SEPARATE) {
			TIFFErrorExt(tif->tif_clientdata, module,
			    "Can not grow image by strips when using separate planes");
			return ((tmsize_t) -1);
		}
		if (!TIFFGrowStrips(tif, 1, module))
			return ((tmsize_t) -1);
		td->td_stripsperimage =
		    TIFFhowmany_32(td->td_imagelength, td->td_rowsperstrip);  
	}