fix: PTS diverge DTS when DTS close to 2pow33 and PTS more than 0 (#1050)

Fixes #1049

Co-authored-by: Joey Parrish <joeyparrish@users.noreply.github.com>

packager/media/formats/mp2t/mp2t_media_parser_unittest.cc

@@ -28,7 +28,9 @@ class Mp2tMediaParserTest : public testing::Test {
       : audio_frame_count_(0),
         video_frame_count_(0),
         video_min_dts_(kNoTimestamp),
-        video_max_dts_(kNoTimestamp) {
+        video_max_dts_(kNoTimestamp),
+        video_min_pts_(kNoTimestamp),
+        video_max_pts_(kNoTimestamp) {
     parser_.reset(new Mp2tMediaParser());
   }
 
@@ -41,6 +43,8 @@ class Mp2tMediaParserTest : public testing::Test {
   int video_frame_count_;
   int64_t video_min_dts_;
   int64_t video_max_dts_;
+  int64_t video_min_pts_;
+  int64_t video_max_pts_;
 
   bool AppendData(const uint8_t* data, size_t length) {
     return parser_->Parse(data, static_cast<int>(length));
@@ -79,6 +83,8 @@ class Mp2tMediaParserTest : public testing::Test {
         ++video_frame_count_;
         if (video_min_dts_ == kNoTimestamp)
           video_min_dts_ = sample->dts();
+        if (video_min_pts_ == kNoTimestamp || video_min_pts_ > sample->pts())
+          video_min_pts_ = sample->pts();
         // Verify timestamps are increasing.
         if (video_max_dts_ == kNoTimestamp)
           video_max_dts_ = sample->dts();
@@ -86,6 +92,9 @@ class Mp2tMediaParserTest : public testing::Test {
           LOG(ERROR) << "Video DTS not strictly increasing.";
           return false;
         }
+        if (video_max_pts_ < sample->pts()) {
+          video_max_pts_ = sample->pts();
+        }
         video_max_dts_ = sample->dts();
       } else {
         LOG(ERROR) << "Missing StreamInfo for track ID " << track_id;
@@ -153,9 +162,9 @@ TEST_F(Mp2tMediaParserTest, UnalignedAppend512_H265) {
 }
 
 TEST_F(Mp2tMediaParserTest, TimestampWrapAround) {
-  // "bear-640x360.ts" has been transcoded from bear-640x360.mp4 by applying a
+  // "bear-640x360_ptszero_dtswraparound.ts" has been transcoded from
-  // time offset of 95442s (close to 2^33 / 90000) which results in timestamps
+  // bear-640x360.mp4 by applying a time offset of 95442s (close to 2^33 /
-  // wrap around in the Mpeg2 TS stream.
+  // 90000) which results in timestamp wrap around in the Mpeg2 TS stream.
   ParseMpeg2TsFile("bear-640x360_ptswraparound.ts", 512);
   EXPECT_TRUE(parser_->Flush());
   EXPECT_EQ(82, video_frame_count_);
@@ -163,6 +172,22 @@ TEST_F(Mp2tMediaParserTest, TimestampWrapAround) {
   EXPECT_GT(video_max_dts_, static_cast<int64_t>(1) << 33);
 }
 
+TEST_F(Mp2tMediaParserTest, PtsZeroDtsWrapAround) {
+  // "bear-640x360.ts" has been transcoded from bear-640x360.mp4 by applying a
+  // dts (close to 2^33 / 90000) and pts 1433 which results in dts
+  // wrap around in the Mpeg2 TS stream but pts does not.
+  ParseMpeg2TsFile("bear-640x360_ptszero_dtswraparound.ts", 512);
+  EXPECT_TRUE(parser_->Flush());
+  EXPECT_EQ(64, video_frame_count_);
+  // DTS was subjected to unroll
+  EXPECT_LT(video_min_dts_, static_cast<int64_t>(1) << 33);
+  EXPECT_GT(video_max_dts_, static_cast<int64_t>(1) << 33);
+  // PTS was not subjected to unroll but was artificially unrolled to be close
+  // to DTS
+  EXPECT_GT(video_min_pts_, static_cast<int64_t>(1) << 33);
+  EXPECT_GT(video_max_pts_, static_cast<int64_t>(1) << 33);
+}
+
 }  // namespace mp2t
 }  // namespace media
 }  // namespace shaka

packager/media/formats/mp2t/ts_section_pes.cc

@@ -5,7 +5,6 @@
 #include "packager/media/formats/mp2t/ts_section_pes.h"
 
 #include "packager/base/logging.h"
-#include "packager/base/strings/string_number_conversions.h"
 #include "packager/media/base/bit_reader.h"
 #include "packager/media/base/timestamp.h"
 #include "packager/media/formats/mp2t/es_parser.h"
@@ -273,14 +272,6 @@ bool TsSectionPes::ParseInternal(const uint8_t* raw_pes, int raw_pes_size) {
   // Convert and unroll the timestamps.
   int64_t media_pts(kNoTimestamp);
   int64_t media_dts(kNoTimestamp);
-  if (is_pts_valid) {
-    int64_t pts = ConvertTimestampSectionToTimestamp(pts_section);
-    if (previous_pts_valid_)
-      pts = UnrollTimestamp(previous_pts_, pts);
-    previous_pts_ = pts;
-    previous_pts_valid_ = true;
-    media_pts = pts;
-  }
   if (is_dts_valid) {
     int64_t dts = ConvertTimestampSectionToTimestamp(dts_section);
     if (previous_dts_valid_)
@@ -289,6 +280,19 @@ bool TsSectionPes::ParseInternal(const uint8_t* raw_pes, int raw_pes_size) {
     previous_dts_valid_ = true;
     media_dts = dts;
   }
+  if (is_pts_valid) {
+    int64_t pts = ConvertTimestampSectionToTimestamp(pts_section);
+    if (previous_pts_valid_) {
+      pts = UnrollTimestamp(previous_pts_, pts);
+    } else {
+      if (media_dts != kNoTimestamp) {
+        pts = UnrollTimestamp(media_dts, pts);
+      }
+    }
+    previous_pts_ = pts;
+    previous_pts_valid_ = true;
+    media_pts = pts;
+  }
 
   // Discard the rest of the PES packet header.
   DCHECK_EQ(bit_reader.bits_available() % 8, 0u);