Fix roundoff issues in i_length.

[vlc] / modules / codec / lpcm.c

diff --git a/modules/codec/lpcm.c b/modules/codec/lpcm.c
index 8e0540afe21162a93a763e6b444455ed8ddae146..2d5c6126f5b2a90bf0286277a1143ad836165053 100644 (file)
--- a/modules/codec/lpcm.c
+++ b/modules/codec/lpcm.c
@@ -9,6 +9,7 @@
  *          Christophe Massiot <massiot@via.ecp.fr>
  *          Gildas Bazin <gbazin@videolan.org>
  *          Lauren Aimar <fenrir _AT_ videolan _DOT_ org >
+ *          Steinar H. Gunderson <steinar+vlc@gunderson.no>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -64,11 +65,13 @@ vlc_module_begin ()
     set_capability( "packetizer", 100 )
     set_callbacks( OpenPacketizer, CloseCommon )
 
+#ifdef ENABLE_SOUT
     add_submodule ()
     set_description( N_("Linear PCM audio encoder") )
     set_capability( "encoder", 100 )
     set_callbacks( OpenEncoder, CloseEncoder )
     add_shortcut( "lpcm" )
+#endif
 
 vlc_module_end ()
 
@@ -91,6 +94,7 @@ struct decoder_sys_t
     int      i_type;
 };
 
+#ifdef ENABLE_SOUT
 struct encoder_sys_t
 {
     int     i_channels;
@@ -101,6 +105,7 @@ struct encoder_sys_t
     int     i_buffer_used;
     int     i_frame_num;
 };
+#endif
 
 /*
  * LPCM DVD header :
@@ -422,6 +427,7 @@ static void CloseCommon( vlc_object_t *p_this )
     free( p_dec->p_sys );
 }
 
+#ifdef ENABLE_SOUT
 /*****************************************************************************
  * OpenEncoder: lpcm encoder construction
  *****************************************************************************/
@@ -431,19 +437,41 @@ static int OpenEncoder( vlc_object_t *p_this )
     encoder_sys_t *p_sys;
 
     /* We only support DVD LPCM yet. */
-    if( p_enc->fmt_out.i_codec != VLC_CODEC_DVD_LPCM ||
-        ( p_enc->fmt_in.audio.i_rate != 48000 &&
-          p_enc->fmt_in.audio.i_rate != 96000 &&
-          p_enc->fmt_in.audio.i_rate != 44100 &&
-          p_enc->fmt_in.audio.i_rate != 32000 ) ||
-       p_enc->fmt_in.audio.i_channels > 8 )
+    if( p_enc->fmt_out.i_codec != VLC_CODEC_DVD_LPCM )
         return VLC_EGENERIC;
 
+    if( p_enc->fmt_in.audio.i_rate != 48000 &&
+        p_enc->fmt_in.audio.i_rate != 96000 &&
+        p_enc->fmt_in.audio.i_rate != 44100 &&
+        p_enc->fmt_in.audio.i_rate != 32000 )
+    {
+        msg_Err( p_enc, "DVD LPCM supports only sample rates of 48, 96, 44.1 or 32 kHz" );
+        return VLC_EGENERIC;
+    }
+
+    if( p_enc->fmt_in.audio.i_channels > 8 )
+    {
+        msg_Err( p_enc, "DVD LPCM supports a maximum of eight channels" );
+        return VLC_EGENERIC;
+    }
+
     /* Allocate the memory needed to store the encoder's structure */
     if( ( p_enc->p_sys = p_sys =
           (encoder_sys_t *)malloc(sizeof(encoder_sys_t)) ) == NULL )
         return VLC_ENOMEM;
 
+    /* In DVD LCPM, a frame is always 150 PTS ticks. */
+    p_sys->i_frame_samples = p_enc->fmt_in.audio.i_rate * 150 / 90000;
+    p_sys->p_buffer = (uint8_t *)malloc(
+        p_sys->i_frame_samples *
+        p_enc->fmt_in.audio.i_channels *
+        p_enc->fmt_in.audio.i_bitspersample);
+    p_sys->i_buffer_used = 0;
+    p_sys->i_frame_num = 0;
+
+    p_sys->i_channels = p_enc->fmt_in.audio.i_channels;
+    p_sys->i_rate = p_enc->fmt_in.audio.i_rate;
+
     p_enc->pf_encode_audio = EncodeFrames;
     p_enc->fmt_in.i_codec = p_enc->fmt_out.i_codec;
 
@@ -453,19 +481,9 @@ static int OpenEncoder( vlc_object_t *p_this )
     p_enc->fmt_out.i_bitrate =
         p_enc->fmt_in.audio.i_channels *
         p_enc->fmt_in.audio.i_rate *
-        p_enc->fmt_in.audio.i_bitspersample;
-    
-    p_sys->i_channels = p_enc->fmt_in.audio.i_channels;
-    p_sys->i_rate = p_enc->fmt_in.audio.i_rate;
-    
-    /* In DVD LCPM, a frame is always 150 PTS ticks. */
-    p_sys->i_frame_samples = p_enc->fmt_in.audio.i_rate * 150 / 90000;
-    p_sys->p_buffer = (uint8_t *)malloc(
-        p_sys->i_frame_samples *
-        p_enc->fmt_in.audio.i_channels *
-        p_enc->fmt_in.audio.i_bitspersample);
-    p_sys->i_buffer_used = 0;
-    p_sys->i_frame_num = 0;
+        p_enc->fmt_in.audio.i_bitspersample *
+        (p_sys->i_frame_samples + LPCM_VOB_HEADER_LEN) /
+        p_sys->i_frame_samples;
 
     return VLC_SUCCESS;
 }
@@ -510,6 +528,8 @@ static block_t *EncodeFrames( encoder_t *p_enc, aout_buffer_t *p_aout_buf )
     case 32000:
         i_freq_code = 3;
         break;
+    default:
+        assert(0);
     }
 
     int i_bytes_consumed = 0;
@@ -534,15 +554,20 @@ static block_t *EncodeFrames( encoder_t *p_enc, aout_buffer_t *p_aout_buf )
 
         memcpy( frame + 6, p_sys->p_buffer, i_kept_bytes );
         memcpy( frame + 6 + i_kept_bytes, p_aout_buf->p_buffer + i_bytes_consumed, i_consume_bytes );
-     
+
         p_sys->i_frame_num++;
         p_sys->i_buffer_used = 0;
         i_bytes_consumed += i_consume_bytes;
 
-        p_block->i_dts = p_block->i_pts = p_aout_buf->i_pts +
+        /* We need to find i_length by means of next_pts due to possible roundoff errors. */
+        mtime_t this_pts = p_aout_buf->i_pts +
             (i * p_sys->i_frame_samples + i_start_offset) * CLOCK_FREQ / p_sys->i_rate;
-        p_block->i_length = p_sys->i_frame_samples * CLOCK_FREQ / p_sys->i_rate;
-    
+        mtime_t next_pts = p_aout_buf->i_pts +
+            ((i + 1) * p_sys->i_frame_samples + i_start_offset) * CLOCK_FREQ / p_sys->i_rate;
+
+        p_block->i_pts = p_block->i_dts = this_pts;
+        p_block->i_length = next_pts - this_pts;
+
         if( !p_first_block )
             p_first_block = p_last_block = p_block;
         else
@@ -556,6 +581,7 @@ static block_t *EncodeFrames( encoder_t *p_enc, aout_buffer_t *p_aout_buf )
 
     return p_first_block;
 }
+#endif
 
 /*****************************************************************************
  *