diff --git a/contrib/packjpg/precomp_jpg.h b/contrib/packjpg/precomp_jpg.h
index c105b78..107aa82 100644
--- a/contrib/packjpg/precomp_jpg.h
+++ b/contrib/packjpg/precomp_jpg.h
@@ -1,6 +1,8 @@
 // Motion JPEG DHT header
 // JPEG DHT Segment for YCrCb omitted from MJPEG data
 
+#define JPG_MAX_MEMORY_SIZE 512 * 1024 * 1024
+
 #define MJPGDHT_LEN 420
 unsigned char MJPGDHT[MJPGDHT_LEN] = {
 0xFF,0xC4,0x01,0xA2,
diff --git a/contrib/packmp3/precomp_mp3.h b/contrib/packmp3/precomp_mp3.h
index 2d7d621..a725fca 100644
--- a/contrib/packmp3/precomp_mp3.h
+++ b/contrib/packmp3/precomp_mp3.h
@@ -3,7 +3,7 @@
 #include "pmp3tbl.h"
 #undef PRECOMP_MP3
 
-#define MP3_MAX_MEMORY_SIZE 64 * 1024 * 1024
+#define MP3_MAX_MEMORY_SIZE 512 * 1024 * 1024
 
 // function to convert MP3 to PMP and vice versa, file to file
 bool pmplib_convert_file2file( char* in, char* out, char* msg );
diff --git a/precomp.cpp b/precomp.cpp
index 792c66d..dbb7d9e 100644
--- a/precomp.cpp
+++ b/precomp.cpp
@@ -4857,7 +4857,7 @@ while (fin_pos < fin_length) {
       unsigned char* jpg_mem_in = NULL;
       unsigned char* jpg_mem_out = NULL;
       unsigned int jpg_mem_out_size = -1;
-      bool in_memory = (recompressed_data_length <= MAX_IO_BUFFER_SIZE);
+      bool in_memory = (recompressed_data_length <= JPG_MAX_MEMORY_SIZE);
       bool recompress_success = false;
 
       if (in_memory) {
@@ -6587,7 +6587,7 @@ void try_decompression_jpg (long long jpg_length, bool progressive_jpg) {
         unsigned char* jpg_mem_in = NULL;
         unsigned char* jpg_mem_out = NULL;
         unsigned int jpg_mem_out_size = -1;
-        bool in_memory = ((jpg_length + MJPGDHT_LEN) <= MAX_IO_BUFFER_SIZE);
+        bool in_memory = ((jpg_length + MJPGDHT_LEN) <= JPG_MAX_MEMORY_SIZE);
 
         if (in_memory) { // small stream => do everything in memory
           jpg_mem_in = new unsigned char[jpg_length + MJPGDHT_LEN];
@@ -6677,7 +6677,10 @@ void try_decompression_jpg (long long jpg_length, bool progressive_jpg) {
 			  brotli_used = false;
 		  }
         } else { // large stream => use temporary files
-          // try to decompress at current position
+		  if (DEBUG_MODE) {
+			printf("JPG too large for brunsli, using packJPG fallback...\n");
+		  }
+		  // try to decompress at current position
           fjpg = tryOpen(tempfile0,"wb");
           seek_64(fin, input_file_pos);
           fast_copy(fin, fjpg, jpg_length);