]> git.sesse.net Git - vlc/blobdiff - modules/codec/lpcm.c
Revert the DVD LPCM header description changes; will be added back later.
[vlc] / modules / codec / lpcm.c
index 123f002a12bb0826cd9d4dfe7b9a4b7141273469..8e62b152d41ac8bfefbc15afed91464ab9fb135e 100644 (file)
@@ -45,6 +45,12 @@ static int  OpenDecoder   ( vlc_object_t * );
 static int  OpenPacketizer( vlc_object_t * );
 static void CloseCommon   ( vlc_object_t * );
 
+#ifdef ENABLE_SOUT
+static int  OpenEncoder   ( vlc_object_t * );
+static void CloseEncoder  ( vlc_object_t * );
+static block_t *EncodeFrames( encoder_t *, aout_buffer_t * );
+#endif
+
 vlc_module_begin ()
 
     set_category( CAT_INPUT )
@@ -58,6 +64,14 @@ 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 ()
 
 
@@ -79,6 +93,19 @@ struct decoder_sys_t
     int      i_type;
 };
 
+#ifdef ENABLE_SOUT
+struct encoder_sys_t
+{
+    int     i_channels;
+    int     i_rate;
+
+    int     i_frame_samples;
+    uint8_t *p_buffer;
+    int     i_buffer_used;
+    int     i_frame_num;
+};
+#endif
+
 /*
  * LPCM DVD header :
  * - frame number (8 bits)
@@ -268,7 +295,7 @@ static void *DecodeFrame( decoder_t *p_dec, block_t **pp_block )
     *pp_block = NULL; /* So the packet doesn't get re-sent */
 
     /* Date management */
-    if( p_block->i_pts > 0 &&
+    if( p_block->i_pts > VLC_TS_INVALID &&
         p_block->i_pts != date_Get( &p_sys->end_date ) )
     {
         date_Set( &p_sys->end_date, p_block->i_pts );
@@ -307,7 +334,7 @@ static void *DecodeFrame( decoder_t *p_dec, block_t **pp_block )
                           p_block->p_buffer );
         break;
     default:
-        assert(0);
+        abort();
     }
 
     if( i_ret || p_block->i_buffer <= p_sys->i_header_size + i_padding )
@@ -360,9 +387,10 @@ static void *DecodeFrame( decoder_t *p_dec, block_t **pp_block )
         if( !p_aout_buffer )
             return NULL;
 
-        p_aout_buffer->start_date = date_Get( &p_sys->end_date );
-        p_aout_buffer->end_date =
-            date_Increment( &p_sys->end_date, i_frame_length );
+        p_aout_buffer->i_pts = date_Get( &p_sys->end_date );
+        p_aout_buffer->i_length =
+            date_Increment( &p_sys->end_date, i_frame_length )
+            - p_aout_buffer->i_pts;
 
         p_block->p_buffer += p_sys->i_header_size + i_padding;
         p_block->i_buffer -= p_sys->i_header_size + i_padding;
@@ -396,6 +424,145 @@ static void CloseCommon( vlc_object_t *p_this )
     free( p_dec->p_sys );
 }
 
+#ifdef ENABLE_SOUT
+/*****************************************************************************
+ * OpenEncoder: lpcm encoder construction
+ *****************************************************************************/
+static int OpenEncoder( vlc_object_t *p_this )
+{
+    encoder_t *p_enc = (encoder_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 )
+        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;
+
+    p_enc->fmt_in.audio.i_bitspersample = 16;
+    p_enc->fmt_in.i_codec = VLC_CODEC_S16B;
+
+    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_frame_samples + LPCM_VOB_HEADER_LEN) /
+        p_sys->i_frame_samples;
+    
+    return VLC_SUCCESS;
+}
+
+/*****************************************************************************
+ * CloseEncoder: lpcm encoder destruction
+ *****************************************************************************/
+static void CloseEncoder ( vlc_object_t *p_this )
+{
+    VLC_UNUSED(p_this);
+}
+
+/*****************************************************************************
+ * EncodeFrames: encode zero or more LCPM audio packets
+ *****************************************************************************/
+static block_t *EncodeFrames( encoder_t *p_enc, aout_buffer_t *p_aout_buf )
+{
+    encoder_sys_t *p_sys = p_enc->p_sys;
+    block_t *p_first_block = NULL, *p_last_block = NULL;
+
+    if( !p_aout_buf || !p_aout_buf->i_buffer ) return NULL;
+
+    const int i_num_frames = ( p_sys->i_buffer_used + p_aout_buf->i_nb_samples ) /
+        p_sys->i_frame_samples;
+    const int i_leftover_samples = ( p_sys->i_buffer_used + p_aout_buf->i_nb_samples ) %
+        p_sys->i_frame_samples;
+    const int i_frame_size = p_sys->i_frame_samples * p_sys->i_channels * 2 + LPCM_VOB_HEADER_LEN;
+    const int i_start_offset = -p_sys->i_buffer_used;
+
+    uint8_t i_freq_code = 0;
+
+    switch( p_sys->i_rate ) {
+    case 48000:
+        i_freq_code = 0;
+        break;
+    case 96000:
+        i_freq_code = 1;
+        break;
+    case 44100:
+        i_freq_code = 2;
+        break;
+    case 32000:
+        i_freq_code = 3;
+        break;
+    }
+
+    int i_bytes_consumed = 0;
+
+    for ( int i = 0; i < i_num_frames; ++i )
+    {
+        block_t *p_block = block_New( p_enc, i_frame_size );
+        if( !p_block )
+            return NULL;
+
+        uint8_t *frame = (uint8_t *)p_block->p_buffer;
+        frame[0] = 1;  /* one frame in packet */
+        frame[1] = 0;
+        frame[2] = 0;  /* no first access unit */
+        frame[3] = (p_sys->i_frame_num + i) & 0x1f;  /* no emphasis, no mute */
+        frame[4] = (i_freq_code << 4) | (p_sys->i_channels - 1);
+        frame[5] = 0x80;  /* neutral dynamic range */
+
+        const int i_consume_samples = p_sys->i_frame_samples - p_sys->i_buffer_used;
+        const int i_kept_bytes = p_sys->i_buffer_used * p_sys->i_channels * 2;
+        const int i_consume_bytes = i_consume_samples * p_sys->i_channels * 2;
+
+        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 +
+            (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;
+    
+        if( !p_first_block )
+            p_first_block = p_last_block = p_block;
+        else
+            p_last_block = p_last_block->p_next = p_block;
+    }
+
+    memcpy( p_sys->p_buffer,
+            p_aout_buf->p_buffer + i_bytes_consumed,
+            i_leftover_samples * p_sys->i_channels * 2 );
+    p_sys->i_buffer_used = i_leftover_samples;
+
+    return p_first_block;
+}
+#endif
+
 /*****************************************************************************
  *
  *****************************************************************************/