From 8808aad5292208579410f6160de4bff387772d61 Mon Sep 17 00:00:00 2001
From: Max Kellermann <max@duempel.org>
Date: Sat, 23 Aug 2014 15:27:21 +0200
Subject: [PATCH] decoder/dsdiff: implement seeking
---
NEWS | 2 +-
src/decoder/plugins/DsdiffDecoderPlugin.cxx | 33 ++++++++++++++++++++-
2 files changed, 33 insertions(+), 2 deletions(-)
diff --git a/NEWS b/NEWS
index 26dbce533..0abb97371 100644
--- a/NEWS
+++ b/NEWS
@@ -42,7 +42,7 @@ ver 0.19 (not yet released)
- audiofile: support scanning remote files
- audiofile: log libaudiofile errors
- dsdiff, dsf: report bit rate
- - dsf: implement seeking
+ - dsdiff, dsf: implement seeking
- dsf: support DSD512
- dsf: support multi-channel files
- dsf: fix big-endian bugs
diff --git a/src/decoder/plugins/DsdiffDecoderPlugin.cxx b/src/decoder/plugins/DsdiffDecoderPlugin.cxx
index de72a0644..37dabc72d 100644
--- a/src/decoder/plugins/DsdiffDecoderPlugin.cxx
+++ b/src/decoder/plugins/DsdiffDecoderPlugin.cxx
@@ -350,6 +350,18 @@ bit_reverse_buffer(uint8_t *p, uint8_t *end)
*p = bit_reverse(*p);
}
+static offset_type
+TimeToFrame(double t, unsigned sample_rate)
+{
+ return offset_type(t * sample_rate / 8);
+}
+
+static offset_type
+TimeToOffset(double t, unsigned channels, unsigned sample_rate)
+{
+ return TimeToFrame(t, sample_rate) * channels;
+}
+
/**
* Decode one "DSD" chunk.
*/
@@ -358,6 +370,8 @@ dsdiff_decode_chunk(Decoder &decoder, InputStream &is,
unsigned channels, unsigned sample_rate,
const offset_type total_bytes)
{
+ const offset_type start_offset = is.GetOffset();
+
uint8_t buffer[8192];
const size_t sample_size = sizeof(buffer[0]);
@@ -368,6 +382,23 @@ dsdiff_decode_chunk(Decoder &decoder, InputStream &is,
auto cmd = decoder_get_command(decoder);
for (offset_type remaining_bytes = total_bytes;
remaining_bytes >= frame_size && cmd != DecoderCommand::STOP;) {
+ if (cmd == DecoderCommand::SEEK) {
+ double t = decoder_seek_where(decoder);
+ offset_type offset = TimeToOffset(t, channels,
+ sample_rate);
+ if (offset >= total_bytes) {
+ decoder_command_finished(decoder);
+ break;
+ }
+
+ if (dsdlib_skip_to(&decoder, is,
+ start_offset + offset)) {
+ decoder_command_finished(decoder);
+ remaining_bytes = total_bytes - offset;
+ } else
+ decoder_seek_error(decoder);
+ }
+
/* see how much aligned data from the remaining chunk
fits into the local buffer */
size_t now_size = buffer_size;
@@ -417,7 +448,7 @@ dsdiff_stream_decode(Decoder &decoder, InputStream &is)
(float) metadata.sample_rate;
/* success: file was recognized */
- decoder_initialized(decoder, audio_format, false, songtime);
+ decoder_initialized(decoder, audio_format, is.IsSeekable(), songtime);
/* every iteration of the following loop decodes one "DSD"
chunk from a DFF file */