Support decompression of JP2 as well as JPEG2000 codestreams.

diff --git a/src/util.cc b/src/util.cc
index 86d1bc87d2810e0bfe7f3632e4509b586015447e..d972d8cec270c212c3143f9289e0482d217e64f5 100644 (file)
--- a/src/util.cc
+++ b/src/util.cc
@@ -204,17 +204,43 @@ dcp::content_kind_from_string (string kind)
 shared_ptr<dcp::XYZImage>
 dcp::decompress_j2k (uint8_t* data, int64_t size, int reduce)
 {
-       opj_dinfo_t* decoder = opj_create_decompress (CODEC_J2K);
+       uint8_t const jp2_magic[] = {
+               0x00,
+               0x00,
+               0x00,
+               0x0c,
+               'j',
+               'P',
+               0x20,
+               0x20
+       };
+       
+       OPJ_CODEC_FORMAT format = CODEC_J2K;
+       if (size >= int (sizeof (jp2_magic)) && memcmp (data, jp2_magic, sizeof (jp2_magic)) == 0) {
+               format = CODEC_JP2;
+       }
+       
+       opj_dinfo_t* decoder = opj_create_decompress (format);
+       if (!decoder) {
+               boost::throw_exception (DCPReadError ("could not create JPEG2000 decompresser"));
+       }
        opj_dparameters_t parameters;
        opj_set_default_decoder_parameters (&parameters);
        parameters.cp_reduce = reduce;
        opj_setup_decoder (decoder, &parameters);
        opj_cio_t* cio = opj_cio_open ((opj_common_ptr) decoder, data, size);
+       if (!cio) {
+               boost::throw_exception (DCPReadError ("could not create JPEG2000 memory stream"));
+       }
        opj_image_t* image = opj_decode (decoder, cio);
        if (!image) {
                opj_destroy_decompress (decoder);
                opj_cio_close (cio);
-               boost::throw_exception (DCPReadError (String::compose ("could not decode JPEG2000 codestream of %1 bytes.", size)));
+               if (format == CODEC_J2K) {
+                       boost::throw_exception (DCPReadError (String::compose ("could not decode JPEG2000 codestream of %1 bytes.", size)));
+               } else {
+                       boost::throw_exception (DCPReadError (String::compose ("could not decode JP2 file of %1 bytes.", size)));
+               }
        }
 
        opj_destroy_decompress (decoder);