Simplify rms(): merge a few operations in the same statement

[ffmpeg] / libavcodec / ac3_parser.c

diff --git a/libavcodec/ac3_parser.c b/libavcodec/ac3_parser.c
index 667c6d3821a7c8889ede8d17cd5e5fe4f16616f7..b9a25abc424bafc29c416f995a2938566f87ff41 100644 (file)
--- a/libavcodec/ac3_parser.c
+++ b/libavcodec/ac3_parser.c
@@ -1,5 +1,5 @@
 /*
- * AC3 parser
+ * AC-3 parser
  * Copyright (c) 2003 Fabrice Bellard.
  * Copyright (c) 2003 Michael Niedermayer.
  *
@@ -33,18 +33,6 @@ static const uint8_t eac3_blocks[4] = {
     1, 2, 3, 6
 };
 
-/**
- * Table for center mix levels
- * reference: Section 5.4.2.4 cmixlev
- */
-static const uint8_t center_levels[4] = { 2, 3, 4, 3 };
-
-/**
- * Table for surround mix levels
- * reference: Section 5.4.2.5 surmixlev
- */
-static const uint8_t surround_levels[4] = { 2, 4, 0, 4 };
-
 
 int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
 {
@@ -63,6 +51,10 @@ int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
 
     hdr->num_blocks = 6;
 
+    /* set default mix levels */
+    hdr->center_mix_level   = 1;  // -4.5dB
+    hdr->surround_mix_level = 1;  // -6.0dB
+
     if(hdr->bitstream_id <= 10) {
         /* Normal AC-3 */
         hdr->crc1 = get_bits(gbc, 16);
@@ -79,17 +71,13 @@ int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
         skip_bits(gbc, 3); // skip bitstream mode
         hdr->channel_mode = get_bits(gbc, 3);
 
-        /* set default mix levels */
-        hdr->center_mix_level   = 3;  // -4.5dB
-        hdr->surround_mix_level = 4;  // -6.0dB
-
         if(hdr->channel_mode == AC3_CHMODE_STEREO) {
             skip_bits(gbc, 2); // skip dsurmod
         } else {
             if((hdr->channel_mode & 1) && hdr->channel_mode != AC3_CHMODE_MONO)
-                hdr->center_mix_level = center_levels[get_bits(gbc, 2)];
+                hdr->center_mix_level = get_bits(gbc, 2);
             if(hdr->channel_mode & 4)
-                hdr->surround_mix_level = surround_levels[get_bits(gbc, 2)];
+                hdr->surround_mix_level = get_bits(gbc, 2);
         }
         hdr->lfe_on = get_bits1(gbc);
 
@@ -99,6 +87,7 @@ int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
         hdr->channels = ff_ac3_channels_tab[hdr->channel_mode] + hdr->lfe_on;
         hdr->frame_size = ff_ac3_frame_size_tab[frame_size_code][hdr->sr_code] * 2;
         hdr->frame_type = EAC3_FRAME_TYPE_AC3_CONVERT; //EAC3_FRAME_TYPE_INDEPENDENT;
+        hdr->substreamid = 0;
     } else {
         /* Enhanced AC-3 */
         hdr->crc1 = 0;
@@ -106,7 +95,7 @@ int ff_ac3_parse_header(GetBitContext *gbc, AC3HeaderInfo *hdr)
         if(hdr->frame_type == EAC3_FRAME_TYPE_RESERVED)
             return AC3_PARSE_ERROR_FRAME_TYPE;
 
-        skip_bits(gbc, 3); // skip substream id
+        hdr->substreamid = get_bits(gbc, 3);
 
         hdr->frame_size = (get_bits(gbc, 11) + 1) << 1;
         if(hdr->frame_size < AC3_HEADER_SIZE)
@@ -203,5 +192,5 @@ AVCodecParser ac3_parser = {
     sizeof(AACAC3ParseContext),
     ac3_parse_init,
     ff_aac_ac3_parse,
-    NULL,
+    ff_parse_close,
 };