AI: Only support AAC/MP3/Opus audio codec. v7.0.102 (#4516)

.augment-guidelines

@@ -923,3 +923,10 @@ faq:
       Why not fixed: Properly fixing this requires significant changes to WebRTC signaling protocol, heartbeat mechanisms,
       and session management across server and all client SDKs. The complexity and maintenance cost is too high for this edge case.
 
+  pcm_audio_not_supported:
+    question: "PCM audio codec not working in RTMP/FLV streaming"
+    answer: |
+      PCM audio codec is not supported in SRS. Only AAC, MP3, and Opus audio codecs are supported for RTMP/FLV streaming.
+      As of v7.0.102 (#4516), SRS explicitly returns an error for unsupported audio codecs instead of silently ignoring them.
+      Solution: Use FFmpeg to convert PCM audio to AAC: ffmpeg -i input -c:v copy -c:a aac -b:a 128k -f flv rtmp://server/live/stream
+

trunk/doc/CHANGELOG.md

@@ -7,7 +7,8 @@ The changelog for SRS.
 <a name="v7-changes"></a>
 
 ## SRS 7.0 Changelog
-* v7.0, 2025-11-04, AI: Fix AAC audio sample rate reporting in API. v7.0.101 (#4518)
+* v7.0, 2025-10-22, AI: Only support AAC/MP3/Opus audio codec. v7.0.102 (#4516)
+* v7.0, 2025-10-22, AI: Fix AAC audio sample rate reporting in API. v7.0.101 (#4518)
 * v7.0, 2025-10-20, Merge [#4537](https://github.com/ossrs/srs/pull/4537): Forward: Reject RTMPS destinations with clear error message. v7.0.100 (#4537)
 * v7.0, 2025-10-17, Merge [#4534](https://github.com/ossrs/srs/pull/4534): HLS: Fix a iterator bug in hls_ctx cleanup function. v7.0.99 (#4534)
 * v7.0, 2025-10-16, Merge [#4530](https://github.com/ossrs/srs/pull/4530): fix crash issue caused by reload configuration file. v7.0.98 (#4530)

trunk/src/core/srs_core_version7.hpp

@@ -9,6 +9,6 @@
 
 #define VERSION_MAJOR 7
 #define VERSION_MINOR 0
-#define VERSION_REVISION 101
+#define VERSION_REVISION 102
 
 #endif

trunk/src/kernel/srs_kernel_packet.cpp

@@ -414,7 +414,7 @@ srs_error_t SrsFormat::on_audio(int64_t timestamp, char *data, int size)
     SrsAudioCodecId codec = (SrsAudioCodecId)((v >> 4) & 0x0f);
 
     if (codec != SrsAudioCodecIdMP3 && codec != SrsAudioCodecIdAAC && codec != SrsAudioCodecIdOpus) {
-        return err;
+        return srs_error_new(ERROR_RTC_RTP_MUXER, "unsupported audio codec=%d(%s)", codec, srs_audio_codec_id2str(codec).c_str());
     }
 
     bool fresh = !acodec_;

trunk/src/utest/srs_utest_kernel.cpp

@@ -4474,13 +4474,27 @@ VOID TEST(KernelCodecTest, AudioFormat)
 {
     srs_error_t err;
 
+    // Test edge cases with NULL/empty audio data
     if (true) {
         SrsFormat f;
         HELPER_EXPECT_SUCCESS(f.initialize());
 
+        // NULL data should return success (early return)
         HELPER_EXPECT_SUCCESS(f.on_audio(0, NULL, 0));
+        // Zero size should return success (early return)
         HELPER_EXPECT_SUCCESS(f.on_audio(0, (char *)"\x00", 0));
-        HELPER_EXPECT_SUCCESS(f.on_audio(0, (char *)"\x00", 1));
+        // Single byte with valid codec (MP3: 0x2F = codec ID 2) should succeed
+        HELPER_EXPECT_SUCCESS(f.on_audio(0, (char *)"\x2F", 1));
+    }
+
+    // Test that unsupported codec (PCM) now returns error
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // PCM codec (0x00) should now return error
+        err = f.on_audio(0, (char *)"\x00", 1);
+        HELPER_EXPECT_FAILED(err);
     }
 
     // For MP3
@@ -4604,6 +4618,111 @@ VOID TEST(KernelCodecTest, AudioFormat)
     }
 }
 
+VOID TEST(KernelCodecTest, UnsupportedAudioCodecs)
+{
+    srs_error_t err;
+
+    // Test PCM codec (codec ID 0 = Linear PCM, platform endian)
+    // Should return error instead of silently ignoring
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // PCM audio: 0x0F = (0 << 4) | 0x0F (codec=0, 44kHz, 16-bit, stereo)
+        err = f.on_audio(0, (char *)"\x0F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_); // acodec_ should remain NULL
+    }
+
+    // Test PCM little endian codec (codec ID 3)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // PCM little endian: 0x3F = (3 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\x3F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Test ADPCM codec (codec ID 1)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // ADPCM: 0x1F = (1 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\x1F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Test Speex codec (codec ID 11)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // Speex: 0xBF = (11 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\xBF\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Test Nellymoser codec (codec ID 6)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // Nellymoser: 0x6F = (6 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\x6F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Test G.711 A-law codec (codec ID 7)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // G.711 A-law: 0x7F = (7 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\x7F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Test G.711 mu-law codec (codec ID 8)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // G.711 mu-law: 0x8F = (8 << 4) | 0x0F
+        err = f.on_audio(0, (char *)"\x8F\x00\x01\x02", 4);
+        HELPER_EXPECT_FAILED(err);
+        EXPECT_TRUE(NULL == f.acodec_);
+    }
+
+    // Verify that supported codecs still work: AAC (codec ID 10)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // AAC sequence header should still work
+        HELPER_EXPECT_SUCCESS(f.on_audio(0, (char *)"\xAF\x00\x12\x10", 4));
+        EXPECT_TRUE(NULL != f.acodec_);
+        EXPECT_EQ(SrsAudioCodecIdAAC, f.acodec_->id_);
+    }
+
+    // Verify that supported codecs still work: MP3 (codec ID 2)
+    if (true) {
+        SrsFormat f;
+        HELPER_EXPECT_SUCCESS(f.initialize());
+
+        // MP3: 0x2F = (2 << 4) | 0x0F
+        HELPER_EXPECT_SUCCESS(f.on_audio(0, (char *)"\x2F\x00", 2));
+        EXPECT_TRUE(NULL != f.acodec_);
+        EXPECT_EQ(SrsAudioCodecIdMP3, f.acodec_->id_);
+    }
+}
+
 VOID TEST(KernelCodecTest, VideoFormatSepcial)
 {
     srs_error_t err;