X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavcodec%2Fmpegaudiodecheader.c;h=428137ddaf22306f0dc2bc0c16175afafcc6a5c3;hb=ad0e31f1346bacdb04341a07375ff597dea8b2e2;hp=0b75e82e652686e9525cc9f6b1859bdfc8490a9b;hpb=4bd8e17c8d371dc05af63b15c11342e40184df61;p=ffmpeg

diff --git a/libavcodec/mpegaudiodecheader.c b/libavcodec/mpegaudiodecheader.c
index 0b75e82e652..428137ddaf2 100644
--- a/libavcodec/mpegaudiodecheader.c
+++ b/libavcodec/mpegaudiodecheader.c
@@ -1,26 +1,26 @@
 /*
  * MPEG Audio header decoder
- * Copyright (c) 2001, 2002 Fabrice Bellard.
+ * Copyright (c) 2001, 2002 Fabrice Bellard
  *
- * This file is part of FFmpeg.
+ * This file is part of Libav.
  *
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
- * FFmpeg is distributed in the hope that it will be useful,
+ * Libav is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
- * License along with FFmpeg; if not, write to the Free Software
+ * License along with Libav; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
 /**
- * @file mpegaudiodecheader.c
+ * @file
  * MPEG Audio header decoder.
  */
 
@@ -28,9 +28,10 @@
 #include "avcodec.h"
 #include "mpegaudio.h"
 #include "mpegaudiodata.h"
+#include "mpegaudiodecheader.h"
 
 
-int decode_header(MPADecodeContext *s, uint32_t header)
+int avpriv_mpegaudio_decode_header(MPADecodeHeader *s, uint32_t header)
 {
     int sample_rate, frame_size, mpeg25, padding;
     int sample_rate_index, bitrate_index;
@@ -45,7 +46,7 @@ int decode_header(MPADecodeContext *s, uint32_t header)
     s->layer = 4 - ((header >> 17) & 3);
     /* extract frequency */
     sample_rate_index = (header >> 10) & 3;
-    sample_rate = ff_mpa_freq_tab[sample_rate_index] >> (s->lsf + mpeg25);
+    sample_rate = avpriv_mpa_freq_tab[sample_rate_index] >> (s->lsf + mpeg25);
     sample_rate_index += 3 * (s->lsf + mpeg25);
     s->sample_rate_index = sample_rate_index;
     s->error_protection = ((header >> 16) & 1) ^ 1;
@@ -66,7 +67,7 @@ int decode_header(MPADecodeContext *s, uint32_t header)
         s->nb_channels = 2;
 
     if (bitrate_index != 0) {
-        frame_size = ff_mpa_bitrate_tab[s->lsf][s->layer - 1][bitrate_index];
+        frame_size = avpriv_mpa_bitrate_tab[s->lsf][s->layer - 1][bitrate_index];
         s->bit_rate = frame_size * 1000;
         switch(s->layer) {
         case 1:
@@ -90,20 +91,56 @@ int decode_header(MPADecodeContext *s, uint32_t header)
     }
 
 #if defined(DEBUG)
-    dprintf(s->avctx, "layer%d, %d Hz, %d kbits/s, ",
+    av_dlog(NULL, "layer%d, %d Hz, %d kbits/s, ",
            s->layer, s->sample_rate, s->bit_rate);
     if (s->nb_channels == 2) {
         if (s->layer == 3) {
             if (s->mode_ext & MODE_EXT_MS_STEREO)
-                dprintf(s->avctx, "ms-");
+                av_dlog(NULL, "ms-");
             if (s->mode_ext & MODE_EXT_I_STEREO)
-                dprintf(s->avctx, "i-");
+                av_dlog(NULL, "i-");
         }
-        dprintf(s->avctx, "stereo");
+        av_dlog(NULL, "stereo");
     } else {
-        dprintf(s->avctx, "mono");
+        av_dlog(NULL, "mono");
     }
-    dprintf(s->avctx, "\n");
+    av_dlog(NULL, "\n");
 #endif
     return 0;
 }
+
+int avpriv_mpa_decode_header(AVCodecContext *avctx, uint32_t head, int *sample_rate, int *channels, int *frame_size, int *bit_rate)
+{
+    MPADecodeHeader s1, *s = &s1;
+
+    if (ff_mpa_check_header(head) != 0)
+        return -1;
+
+    if (avpriv_mpegaudio_decode_header(s, head) != 0) {
+        return -1;
+    }
+
+    switch(s->layer) {
+    case 1:
+        avctx->codec_id = CODEC_ID_MP1;
+        *frame_size = 384;
+        break;
+    case 2:
+        avctx->codec_id = CODEC_ID_MP2;
+        *frame_size = 1152;
+        break;
+    default:
+    case 3:
+        avctx->codec_id = CODEC_ID_MP3;
+        if (s->lsf)
+            *frame_size = 576;
+        else
+            *frame_size = 1152;
+        break;
+    }
+
+    *sample_rate = s->sample_rate;
+    *channels = s->nb_channels;
+    *bit_rate = s->bit_rate;
+    return s->frame_size;
+}