ad_spdif: fix obscure cases of AC3 passthrough

Apparently you set the native sample rate when passing through AC3.
This fixes passthrough with 44100 Hz AC3.

Avoid opening a decoder for this and only open the parser. (Hopefully
DTS will also support this some time in the future or so - having to
open a decoder just to get the profile is dumb.)

1 files changed, 28 insertions, 7 deletions

diff --git a/audio/decode/ad_spdif.c b/audio/decode/ad_spdif.c
index 5ab76e677a..775834ecba 100644
--- a/audio/decode/ad_spdif.c
+++ b/audio/decode/ad_spdif.c
@@ -93,13 +93,34 @@ static int init(struct dec_audio *da, const char *decoder)
     return spdif_ctx->codec_id != AV_CODEC_ID_NONE;
 }
 
-static int determine_codec_profile(struct dec_audio *da, AVPacket *pkt)
+static void determine_codec_params(struct dec_audio *da, AVPacket *pkt,
+                                   int *out_profile, int *out_rate)
 {
     struct spdifContext *spdif_ctx = da->priv;
     int profile = FF_PROFILE_UNKNOWN;
     AVCodecContext *ctx = NULL;
     AVFrame *frame = NULL;
 
+    AVCodecParserContext *parser = av_parser_init(spdif_ctx->codec_id);
+    if (parser) {
+        // Don't make it wait for the next frame.
+        parser->flags |= PARSER_FLAG_COMPLETE_FRAMES;
+
+        ctx = avcodec_alloc_context3(NULL);
+
+        uint8_t *d = NULL;
+        int s = 0;
+        av_parser_parse2(parser, ctx, &d, &s, pkt->data, pkt->size, 0, 0, 0);
+        *out_profile = profile = ctx->profile;
+        *out_rate = ctx->sample_rate;
+
+        av_free(ctx);
+        av_parser_close(parser);
+    }
+
+    if (profile != FF_PROFILE_UNKNOWN || spdif_ctx->codec_id != AV_CODEC_ID_DTS)
+        return;
+
     AVCodec *codec = avcodec_find_decoder(spdif_ctx->codec_id);
     if (!codec)
         goto done;
@@ -123,7 +144,8 @@ static int determine_codec_profile(struct dec_audio *da, AVPacket *pkt)
     if (avcodec_receive_frame(ctx, frame) < 0)
         goto done;
 
-    profile = ctx->profile;
+    *out_profile = profile = ctx->profile;
+    *out_rate = ctx->sample_rate;
 
 done:
     av_frame_free(&frame);
@@ -133,8 +155,6 @@ done:
 
     if (profile == FF_PROFILE_UNKNOWN)
         MP_WARN(da, "Failed to parse codec profile.\n");
-
-    return profile;
 }
 
 static int init_filter(struct dec_audio *da, AVPacket *pkt)
@@ -142,8 +162,9 @@ static int init_filter(struct dec_audio *da, AVPacket *pkt)
     struct spdifContext *spdif_ctx = da->priv;
 
     int profile = FF_PROFILE_UNKNOWN;
-    if (spdif_ctx->codec_id == AV_CODEC_ID_DTS)
-        profile = determine_codec_profile(da, pkt);
+    int c_rate = 0;
+    determine_codec_params(da, pkt, &profile, &c_rate);
+    MP_VERBOSE(da, "In: profile=%d samplerate=%d\n", profile, c_rate);
 
     AVFormatContext *lavf_ctx  = avformat_alloc_context();
     if (!lavf_ctx)
@@ -189,7 +210,7 @@ static int init_filter(struct dec_audio *da, AVPacket *pkt)
         break;
     case AV_CODEC_ID_AC3:
         sample_format                   = AF_FORMAT_S_AC3;
-        samplerate                      = 48000;
+        samplerate                      = c_rate > 0 ? c_rate : 48000;
         num_channels                    = 2;
         break;
     case AV_CODEC_ID_DTS: {