diff --git a/src/ddt/ddt_v2.c b/src/ddt/ddt_v2.c
index 73874aa..02eaedd 100644
--- a/src/ddt/ddt_v2.c
+++ b/src/ddt/ddt_v2.c
@@ -1305,11 +1305,11 @@ bool set_ddt_multi_level_v2(aaruformatContext *ctx, uint64_t sector_address, boo
 
             // Prepare DDT header for the never-written cached table
             memset(&ddt_header, 0, sizeof(DdtHeader2));
-            ddt_header.identifier          = DeDuplicationTable2;
-            ddt_header.type                = UserData;
-            ddt_header.compression         = None;  // Use no compression for simplicity
-            ddt_header.levels              = ctx->userDataDdtHeader.levels;
-            ddt_header.tableLevel          = ctx->userDataDdtHeader.tableLevel + 1;
+            ddt_header.identifier  = DeDuplicationTable2;
+            ddt_header.type        = UserData;
+            ddt_header.compression = ctx->compression_enabled ? Lzma : None;  // Use no compression for simplicity
+            ddt_header.levels      = ctx->userDataDdtHeader.levels;
+            ddt_header.tableLevel  = ctx->userDataDdtHeader.tableLevel + 1;
             ddt_header.previousLevelOffset = ctx->primaryDdtOffset;
             ddt_header.negative            = ctx->userDataDdtHeader.negative;
             ddt_header.blocks              = items_per_ddt_entry;
@@ -1327,8 +1327,6 @@ bool set_ddt_multi_level_v2(aaruformatContext *ctx, uint64_t sector_address, boo
             else
                 ddt_header.length = items_per_ddt_entry * sizeof(uint32_t);
 
-            ddt_header.cmpLength = ddt_header.length;
-
             // Calculate CRC64 of the data
             crc64_context = aaruf_crc64_init();
             if(crc64_context == NULL)
@@ -1339,13 +1337,63 @@ bool set_ddt_multi_level_v2(aaruformatContext *ctx, uint64_t sector_address, boo
             }
 
             if(ctx->userDataDdtHeader.sizeType == SmallDdtSizeType)
-                aaruf_crc64_update(crc64_context, (uint8_t *)ctx->cachedSecondaryDdtSmall, ddt_header.length);
+                aaruf_crc64_update(crc64_context, (uint8_t *)ctx->cachedSecondaryDdtSmall, (uint32_t)ddt_header.length);
             else
-                aaruf_crc64_update(crc64_context, (uint8_t *)ctx->cachedSecondaryDdtBig, ddt_header.length);
+                aaruf_crc64_update(crc64_context, (uint8_t *)ctx->cachedSecondaryDdtBig, (uint32_t)ddt_header.length);
 
             aaruf_crc64_final(crc64_context, &crc64);
-            ddt_header.crc64    = crc64;
-            ddt_header.cmpCrc64 = crc64;
+            ddt_header.crc64 = crc64;
+
+            uint8_t *cmp_buffer                              = NULL;
+            uint8_t  lzma_properties[LZMA_PROPERTIES_LENGTH] = {0};
+
+            if(ddt_header.compression == None)
+            {
+                if(ctx->userDataDdtHeader.sizeType == SmallDdtSizeType)
+                    cmp_buffer = (uint8_t *)ctx->cachedSecondaryDdtSmall;
+                else
+                    cmp_buffer = (uint8_t *)ctx->cachedSecondaryDdtBig;
+                ddt_header.cmpCrc64 = ddt_header.crc64;
+            }
+            else
+            {
+                cmp_buffer = malloc((size_t)ddt_header.length * 2);  // Allocate double size for compression
+                if(cmp_buffer == NULL)
+                {
+                    TRACE("Failed to allocate memory for secondary DDT v2 compression");
+                    return AARUF_ERROR_NOT_ENOUGH_MEMORY;
+                }
+
+                size_t dst_size   = (size_t)ddt_header.length * 2 * 2;
+                size_t props_size = LZMA_PROPERTIES_LENGTH;
+                aaruf_lzma_encode_buffer(
+                    cmp_buffer, &dst_size,
+                    ctx->userDataDdtHeader.sizeType == SmallDdtSizeType ? (uint8_t *)ctx->cachedSecondaryDdtSmall
+                                                                        : (uint8_t *)ctx->cachedSecondaryDdtBig,
+                    ddt_header.length, lzma_properties, &props_size, 9, ctx->lzma_dict_size, 4, 0, 2, 273, 8);
+
+                ddt_header.cmpLength = (uint32_t)dst_size;
+
+                if(ddt_header.cmpLength >= ddt_header.length)
+                {
+                    ddt_header.compression = None;
+                    free(cmp_buffer);
+                    if(ctx->userDataDdtHeader.sizeType == SmallDdtSizeType)
+                        cmp_buffer = (uint8_t *)ctx->cachedSecondaryDdtSmall;
+                    else
+                        cmp_buffer = (uint8_t *)ctx->cachedSecondaryDdtBig;
+                }
+            }
+
+            if(ddt_header.compression == None)
+            {
+                ddt_header.cmpLength = ddt_header.length;
+                ddt_header.cmpCrc64  = ddt_header.crc64;
+            }
+            else
+                ddt_header.cmpCrc64 = aaruf_crc64_data(cmp_buffer, (uint32_t)ddt_header.cmpLength);
+
+            if(ddt_header.compression == Lzma) ddt_header.cmpLength += LZMA_PROPERTIES_LENGTH;
 
             // Write header
             written_bytes = fwrite(&ddt_header, sizeof(DdtHeader2), 1, ctx->imageStream);
@@ -1357,18 +1405,17 @@ bool set_ddt_multi_level_v2(aaruformatContext *ctx, uint64_t sector_address, boo
             }
 
             // Write data
-            if(ctx->userDataDdtHeader.sizeType == SmallDdtSizeType)
-                written_bytes = fwrite(ctx->cachedSecondaryDdtSmall, ddt_header.length, 1, ctx->imageStream);
-            else
-                written_bytes = fwrite(ctx->cachedSecondaryDdtBig, ddt_header.length, 1, ctx->imageStream);
+            if(ddt_header.compression == Lzma) fwrite(lzma_properties, LZMA_PROPERTIES_LENGTH, 1, ctx->imageStream);
 
-            if(written_bytes != 1)
+            if(fwrite(cmp_buffer, ddt_header.cmpLength, 1, ctx->imageStream) != 1)
             {
                 FATAL("Could not write never-written DDT data to file.");
                 TRACE("Exiting set_ddt_multi_level_v2() = false");
                 return false;
             }
 
+            if(ddt_header.compression == Lzma) free(cmp_buffer);
+
             // Add index entry for the newly written secondary DDT
             IndexEntry new_ddt_entry;
             new_ddt_entry.blockType = DeDuplicationTable2;