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Diffstat (limited to 'src/demuxers/demux_mpgaudio.c')
-rw-r--r--src/demuxers/demux_mpgaudio.c270
1 files changed, 189 insertions, 81 deletions
diff --git a/src/demuxers/demux_mpgaudio.c b/src/demuxers/demux_mpgaudio.c
index 549005bef..cf410eed8 100644
--- a/src/demuxers/demux_mpgaudio.c
+++ b/src/demuxers/demux_mpgaudio.c
@@ -33,7 +33,7 @@
#include <string.h>
#include <stdlib.h>
-#define LOG_MODULE "demux_mpeg_audio"
+#define LOG_MODULE "demux_mpgaudio"
#define LOG_VERBOSE
/*
#define LOG
@@ -51,8 +51,8 @@
* the second mp3 frame is sent to the decoder
*/
#define NUM_PREVIEW_BUFFERS 2
+#define NUM_VALID_FRAMES 3
-#define WRAP_THRESHOLD 120000
#define FOURCC_TAG BE_FOURCC
#define RIFF_CHECK_BYTES 1024
@@ -77,16 +77,16 @@
/* mp3 frame struct */
typedef struct {
/* header */
- double duration;
- uint32_t size; /* in bytes */
+ double duration; /* in milliseconds */
+ uint32_t size; /* in bytes; including padding */
uint32_t bitrate; /* in bit per second */
uint16_t freq; /* in Hz */
-
uint8_t layer;
-
uint8_t version_idx:2; /* 0: mpeg1, 1: mpeg2, 2: mpeg2.5 */
uint8_t lsf_bit:1;
uint8_t channel_mode:3;
+ uint8_t padding:3; /* in bytes */
+ uint8_t is_free_bitrate:1;
} mpg_audio_frame_t;
/* Xing Vbr Header struct */
@@ -125,7 +125,13 @@ typedef struct {
int br; /* bitrate in bits/second */
uint32_t blocksize;
+ /* current mp3 frame */
mpg_audio_frame_t cur_frame;
+
+ /* next mp3 frame, used when the frame size cannot be computed from the
+ * current frame header */
+ mpg_audio_frame_t next_frame;
+
double cur_time; /* in milliseconds */
off_t mpg_frame_start; /* offset */
@@ -135,7 +141,15 @@ typedef struct {
int check_vbr_header;
xing_header_t *xing_header;
vbri_header_t *vbri_header;
-
+
+ int found_next_frame:1;
+ int free_bitrate_count;
+ off_t free_bitrate_size; /* use this size if 3 free bitrate frames are encountered */
+ uint8_t next_header[4];
+ int mpg_version;
+ int mpg_layer;
+ int valid_frames;
+
} demux_mpgaudio_t ;
/* demuxer class struct */
@@ -206,14 +220,14 @@ static int parse_frame_header(mpg_audio_frame_t *const frame, const uint8_t *con
const uint32_t head = _X_BE_32(buf);
const uint16_t frame_sync = head >> 21;
- lprintf("header: %08X\n", head);
if (frame_sync != 0x7ff) {
- lprintf("invalid frame sync\n");
+ lprintf("invalid frame sync %08X\n", head);
return 0;
}
+ lprintf("header: %08X\n", head);
frame_header.mpeg25_bit = (head >> 20) & 0x1;
- frame->lsf_bit = (head >> 19) & 0x1;
+ frame->lsf_bit = (head >> 19) & 0x1;
if (!frame_header.mpeg25_bit) {
if (frame->lsf_bit) {
lprintf("reserved mpeg25 lsf combination\n");
@@ -234,14 +248,14 @@ static int parse_frame_header(mpg_audio_frame_t *const frame, const uint8_t *con
}
frame_header.bitrate_idx = (head >> 12) & 0xf;
- if ((frame_header.bitrate_idx == 0) || (frame_header.bitrate_idx == 15)) {
- lprintf("invalid bitrate index\n");
+ if (frame_header.bitrate_idx == 15) {
+ lprintf("invalid bitrate index: %d\n", frame_header.bitrate_idx);
return 0;
}
frame_header.freq_idx = (head >> 10) & 0x3;
if (frame_header.freq_idx == 3) {
- lprintf("invalid frequence index\n");
+ lprintf("invalid frequence index: %d\n", frame_header.freq_idx);
return 0;
}
@@ -274,19 +288,27 @@ static int parse_frame_header(mpg_audio_frame_t *const frame, const uint8_t *con
const uint16_t samples = mp3_samples[frame->version_idx][frame->layer - 1];
frame->bitrate = mp3_bitrates[frame->version_idx][frame->layer - 1][frame_header.bitrate_idx] * 1000;
frame->freq = mp3_freqs[frame->version_idx][frame_header.freq_idx];
-
- frame->size = samples * (frame->bitrate / 8);
- frame->size /= frame->freq;
- /* Padding: only if padding_bit is set; 4 bytes for Layer 1 and 1 byte for others */
- frame->size += ( frame_header.padding_bit ? ( frame->layer == 1 ? 4 : 1 ) : 0 );
-
frame->duration = 1000.0f * (double)samples / (double)frame->freq;
+ frame->padding = ( frame_header.padding_bit ? ( frame->layer == 1 ? 4 : 1 ) : 0 );
+ frame->channel_mode = frame_header.channel_mode;
+
+ if (frame->bitrate > 0) {
+ frame->size = samples * (frame->bitrate / 8);
+ frame->size /= frame->freq;
+ /* Padding: only if padding_bit is set; 4 bytes for Layer 1 and 1 byte for others */
+ frame->size += frame->padding;
+ } else {
+ /* Free bitrate frame, the size of the frame cannot be computed from the header. */
+ frame->is_free_bitrate = 1;
+ frame->size = 0;
+ }
}
- lprintf("mpeg %d, layer %d\n", frame->version_idx + 1, frame->layer);
- lprintf("bitrate: %d bps, samplerate: %d Hz\n", frame->bitrate, frame->freq);
+ lprintf("mpeg %d, layer %d, channel_mode: %d\n", frame->version_idx + 1,
+ frame->layer, frame->channel_mode);
+ lprintf("bitrate: %d bps, output freq: %d Hz\n", frame->bitrate, frame->freq);
lprintf("length: %d bytes, %f ms\n", frame->size, frame->duration);
- lprintf("padding: %d bytes\n", ( frame_header.padding_bit ? ( frame->layer == 1 ? 4 : 1 ) : 0 ));
+ lprintf("padding: %d bytes\n", frame->padding);
return 1;
}
@@ -323,7 +345,7 @@ static xing_header_t* parse_xing_header(mpg_audio_frame_t *frame,
if (!xing)
goto exit_error;
- lprintf("Xing header found\n");
+ lprintf("found Xing header\n");
ptr += 4;
if (ptr >= (buf + bufsize - 4)) goto exit_error;
@@ -414,7 +436,7 @@ static vbri_header_t* parse_vbri_header(mpg_audio_frame_t *frame,
if ((ptr + 4) >= (buf + bufsize)) return 0;
lprintf("Checking %08X\n", *ptr);
if (_X_BE_32(ptr) == VBRI_TAG) {
- lprintf("Vbri header found\n");
+ lprintf("found Vbri header\n");
ptr += 4;
if ((ptr + 22) >= (buf + bufsize)) return 0;
@@ -478,6 +500,7 @@ static vbri_header_t* parse_vbri_header(mpg_audio_frame_t *frame,
}
}
+
/*
* Parse a mp3 frame paylod
* return 1 on success, 0 on error
@@ -488,43 +511,97 @@ static int parse_frame_payload(demux_mpgaudio_t *this,
buf_element_t *buf;
off_t frame_pos, len;
uint64_t pts = 0;
+ int payload_size = 0;
frame_pos = this->input->get_current_pos(this->input) - 4;
- lprintf("frame_pos = %"PRId64"\n", frame_pos);
+ lprintf("frame_pos = %"PRId64", header: %08X\n", frame_pos, _X_BE_32(frame_header));
buf = this->audio_fifo->buffer_pool_alloc(this->audio_fifo);
if (this->cur_frame.size > buf->max_size) {
xprintf(this->stream->xine, XINE_VERBOSITY_LOG,
- "demux_mpgaudio: frame size is greater than fifo buffer size\n");
+ LOG_MODULE ": frame size is greater than fifo buffer size\n");
buf->free_buffer(buf);
return 0;
}
-
- /* the decoder needs the frame header */
- memcpy(buf->mem, frame_header, 4);
- len = this->input->read(this->input, buf->mem + 4, this->cur_frame.size - 4);
- if (len != (this->cur_frame.size - 4)) {
- buf->free_buffer(buf);
- return 0;
+ memcpy(buf->content, frame_header, 4);
+
+ /* compute the payload size */
+ if (this->cur_frame.size > 0) {
+ payload_size = this->cur_frame.size - 4;
+ this->free_bitrate_count = 0;
+ } else if (this->free_bitrate_count >= NUM_VALID_FRAMES) {
+ payload_size = this->free_bitrate_size + this->cur_frame.padding - 4;
+ this->cur_frame.size = payload_size + 4;
+ } else {
+ this->free_bitrate_count++;
+ payload_size = 0;
+ }
+
+ /* Read the payload data. */
+ if (payload_size > 0) {
+ off_t len;
+
+ /* If we know the payload size, it's easy */
+ this->found_next_frame = 0;
+ len = this->input->read(this->input, buf->content + 4, payload_size);
+ if (len != payload_size) {
+ buf->free_buffer(buf);
+ return 0;
+ }
+ } else {
+ /* Search for the beginning of the next frame and deduce the size of the
+ * current frame from the position of the next one. */
+ int payload_size = 0;
+ int max_size = buf->max_size - 4;
+
+ while (payload_size < max_size) {
+ len = this->input->read(this->input, &buf->content[4 + payload_size], 1);
+ if (len != 1) {
+ lprintf("EOF\n");
+ buf->free_buffer(buf);
+ return 0;
+ }
+ payload_size += len;
+
+ if (parse_frame_header(&this->next_frame, &buf->content[payload_size])) {
+ lprintf("found next frame header\n");
+
+ if (this->free_bitrate_size == 0) {
+ this->free_bitrate_size = payload_size - this->cur_frame.padding;
+ }
+
+ /* don't read the frame header twice */
+ this->found_next_frame = 1;
+ memcpy(&this->next_header[0], &buf->content[payload_size], 4);
+ payload_size -= 4;
+ break;
+ }
+ }
+ this->cur_frame.size = payload_size + 4;
+ this->cur_frame.bitrate = 8000 * this->cur_frame.size / this->cur_frame.duration;
+ lprintf("free bitrate: bitrate: %d, frame size: %d\n", this->br, this->cur_frame.size);
}
if (this->check_vbr_header) {
this->check_vbr_header = 0;
this->mpg_frame_start = frame_pos;
- this->xing_header = parse_xing_header(&this->cur_frame, buf->mem, this->cur_frame.size);
+ this->xing_header = parse_xing_header(&this->cur_frame, buf->content, this->cur_frame.size);
if (this->xing_header) {
buf->free_buffer(buf);
+ xprintf(this->stream->xine, XINE_VERBOSITY_LOG,
+ LOG_MODULE ": found Xing header at offset %PRId64\n", frame_pos);
return 1;
}
- this->vbri_header = parse_vbri_header(&this->cur_frame, buf->mem, this->cur_frame.size);
+ this->vbri_header = parse_vbri_header(&this->cur_frame, buf->content, this->cur_frame.size);
if (this->vbri_header) {
buf->free_buffer(buf);
+ xprintf(this->stream->xine, XINE_VERBOSITY_LOG,
+ LOG_MODULE ": found Vbri header at offset %PRId64\n", frame_pos);
return 1;
}
}
-
pts = (int64_t)(this->cur_time * 90.0f);
@@ -533,14 +610,13 @@ static int parse_frame_payload(demux_mpgaudio_t *this,
buf->extra_info->input_time = this->cur_time;
buf->pts = pts;
- buf->size = len + 4;
- buf->content = buf->mem;
+ buf->size = this->cur_frame.size;
buf->type = BUF_AUDIO_MPEG;
buf->decoder_info[0] = 1;
buf->decoder_flags = decoder_flags|BUF_FLAG_FRAME_END;
+ lprintf("send buffer: size=%d, pts=%"PRId64"\n", buf->size, pts);
this->audio_fifo->put(this->audio_fifo, buf);
- lprintf("send buffer: pts=%"PRId64"\n", pts);
this->cur_time += this->cur_frame.duration;
return 1;
}
@@ -604,40 +680,51 @@ static int read_frame_header(demux_mpgaudio_t *this, uint8_t *header_buf, int by
* Parse next mp3 frame
*/
static int demux_mpgaudio_next (demux_mpgaudio_t *this, int decoder_flags, int send_header) {
- uint8_t header_buf[4];
- int bytes = 4;
-
- for (;;) {
-
- if (read_frame_header(this, header_buf, bytes)) {
-
- if (parse_frame_header(&this->cur_frame, header_buf)) {
-
- /* send header buffer */
- if ( send_header ) {
- buf_element_t *buf;
-
- buf = this->audio_fifo->buffer_pool_alloc(this->audio_fifo);
-
- buf->type = BUF_AUDIO_MPEG;
- buf->decoder_flags = BUF_FLAG_HEADER|BUF_FLAG_STDHEADER|BUF_FLAG_FRAME_END;
-
- buf->decoder_info[0] = 0;
- buf->decoder_info[1] = this->cur_frame.freq;
- buf->decoder_info[2] = 0; /* bits_per_sample */
-
- /* Only for channel_mode == 3 (mono) there is one channel, for any other case, there are 2 */
- buf->decoder_info[3] = ( this->cur_frame.channel_mode == 3 ) ? 1 : 2;
-
- buf->size = 0; /* No extra header data */
-
- this->audio_fifo->put(this->audio_fifo, buf);
- }
-
- return parse_frame_payload(this, header_buf, decoder_flags);
-
- } else if ( id3v2_istag(_X_ME_32(header_buf)) ) {
- if (!id3v2_parse_tag(this->input, this->stream, _X_ME_32(header_buf))) {
+ uint8_t buffer[4];
+ uint8_t *header = buffer;
+
+ if (this->found_next_frame) {
+ lprintf("skip header reading\n");
+ header = this->next_header;
+ memcpy(&this->cur_frame, &this->next_frame, sizeof(mpg_audio_frame_t));
+ } else {
+ int bytes = 4;
+ int loose_sync = 0;
+
+ for (;;) {
+ if (!read_frame_header(this, header, bytes))
+ return 0;
+ if (parse_frame_header(&this->cur_frame, header)) {
+ lprintf("frame found\n");
+
+ /* additionnal checks */
+ if ((this->mpg_version == (this->cur_frame.version_idx + 1)) &&
+ (this->mpg_layer == this->cur_frame.layer)) {
+ this->valid_frames++;
+ break;
+ } else {
+ if (this->valid_frames >= NUM_VALID_FRAMES) {
+ lprintf("invalid frame. expected mpeg %d, layer %d\n", this->mpg_version, this->mpg_layer);
+ } else {
+ this->mpg_version = this->cur_frame.version_idx + 1;
+ this->mpg_layer = this->cur_frame.layer;
+ this->valid_frames = 0;
+ break;
+ }
+ }
+ }
+
+ if (!loose_sync) {
+ off_t frame_pos = this->input->get_current_pos(this->input) - 4;
+ loose_sync = 1;
+ xprintf(this->stream->xine, XINE_VERBOSITY_LOG,
+ LOG_MODULE ": loose mp3 sync at offset %"PRId64"\n", frame_pos);
+ }
+ /* the stream is broken, don't keep info about previous frames */
+ this->free_bitrate_size = 0;
+
+ if ( id3v2_istag(header) ) {
+ if (!id3v2_parse_tag(this->input, this->stream, header)) {
xprintf(this->stream->xine, XINE_VERBOSITY_LOG,
LOG_MODULE ": ID3V2 tag parsing error\n");
bytes = 1; /* resync */
@@ -648,12 +735,31 @@ static int demux_mpgaudio_next (demux_mpgaudio_t *this, int decoder_flags, int s
/* skip */
bytes = 1;
}
-
- } else {
- lprintf("read error\n");
- return 0;
}
}
+
+ /* send header buffer */
+ if ( send_header ) {
+ buf_element_t *buf;
+
+ buf = this->audio_fifo->buffer_pool_alloc(this->audio_fifo);
+
+ buf->type = BUF_AUDIO_MPEG;
+ buf->decoder_flags = BUF_FLAG_HEADER|BUF_FLAG_STDHEADER|BUF_FLAG_FRAME_END;
+
+ buf->decoder_info[0] = 0;
+ buf->decoder_info[1] = this->cur_frame.freq;
+ buf->decoder_info[2] = 0; /* bits_per_sample */
+
+ /* Only for channel_mode == 3 (mono) there is one channel, for any other case, there are 2 */
+ buf->decoder_info[3] = ( this->cur_frame.channel_mode == 3 ) ? 1 : 2;
+
+ buf->size = 0; /* No extra header data */
+
+ this->audio_fifo->put(this->audio_fifo, buf);
+ }
+
+ return parse_frame_payload(this, header, decoder_flags);
}
static int demux_mpgaudio_send_chunk (demux_plugin_t *this_gen) {
@@ -776,11 +882,12 @@ static void demux_mpgaudio_send_headers (demux_plugin_t *this_gen) {
*/
this->check_vbr_header = 1;
for (i = 0; i < NUM_PREVIEW_BUFFERS; i++) {
+ lprintf("preview buffer number %d / %d\n", i + 1, NUM_PREVIEW_BUFFERS);
if (!demux_mpgaudio_next (this, BUF_FLAG_PREVIEW, i == 0)) {
break;
}
}
-
+
if (this->xing_header) {
xing_header_t *xing = this->xing_header;
@@ -791,7 +898,7 @@ static void demux_mpgaudio_send_headers (demux_plugin_t *this_gen) {
if (this->stream_length) {
this->br = ((uint64_t)xing->stream_size * 8 * 1000) / this->stream_length;
}
-
+
} else if (this->vbri_header) {
vbri_header_t *vbri = this->vbri_header;
@@ -834,7 +941,7 @@ static void demux_mpgaudio_send_headers (demux_plugin_t *this_gen) {
{
char scratch_buf[256];
static const char mpeg_ver[3][4] = {"1", "2", "2.5"};
-
+
snprintf(scratch_buf, 256, "MPEG %s Layer %1d%s",
mpeg_ver[this->cur_frame.version_idx], this->cur_frame.layer,
(this->xing_header)? " VBR" : " CBR" );
@@ -962,7 +1069,8 @@ static int demux_mpgaudio_seek (demux_plugin_t *this_gen,
/* assume seeking is always perfect... */
this->cur_time = start_time;
this->input->seek (this->input, seek_pos, SEEK_SET);
-
+ this->found_next_frame = 0;
+
if (playing) {
_x_demux_flush_engine(this->stream);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-17 12:14:20 +0000