* rocDecoder/Bitstream reader: Added stream type detection optimization. (#522)

- During stream type evaluation, when we have a high confidence score, we stop and finalize, to avoid unnecessary exhaustive type search.

[ROCm/rocdecode commit: 5f779a6eb7]

projects/rocdecode/CHANGELOG.md

@@ -10,6 +10,8 @@ Full documentation for rocDecode is available at [https://rocm.docs.amd.com/proj
 
 ### Changed
 
+* Bitstream type detection optimization in bitstream reader.
+
 ### Removed
 
 ## rocDecode 0.10.0 for ROCm 6.4

projects/rocdecode/src/bit_stream_reader/es_reader.cpp

@@ -585,6 +585,9 @@ int RocVideoESParser::ProbeStreamType() {
                 break;
             }
         }
+        if (stream_type_score >= STREAM_TYPE_HIGH_CONFIDENCE_SCORE_THRESHOLD) {
+            break;
+        }
     }
 
     if (stream_buf) {
@@ -688,7 +691,7 @@ int RocVideoESParser::CheckAvcEStream(uint8_t *p_stream, int stream_size) {
     if (num_start_codes == 0) {
         score = 0;
     } else {
-        score = sps_present * 25 + pps_present * 25 + idr_slice_present * 15 + slice_present * 15 + first_slice_present * 15;
+        score = sps_present * 25 + pps_present * 25 + idr_slice_present * 20 + slice_present * 15 + first_slice_present * 15;
     }
     return score;
 }
@@ -832,7 +835,7 @@ int RocVideoESParser::CheckHevcEStream(uint8_t *p_stream, int stream_size) {
     if (num_start_codes == 0) {
         score = 0;
     } else {
-        score = vps_present * 20 + sps_present * 20 + pps_present * 20 + rap_slice_present * 15 + slice_present * 15 + first_slice_present * 15;
+        score = vps_present * 15 + sps_present * 20 + pps_present * 20 + rap_slice_present * 15 + slice_present * 15 + first_slice_present * 15;
     }
     return score;
 }

projects/rocdecode/src/bit_stream_reader/es_reader.h

@@ -42,6 +42,7 @@ enum {
 
 #define STREAM_PROBE_SIZE 2 * 1024
 #define STREAM_TYPE_SCORE_THRESHOLD 50
+#define STREAM_TYPE_HIGH_CONFIDENCE_SCORE_THRESHOLD 90
 
 class RocVideoESParser {
     public: