+/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
+
+/** \file opus_afh.c Audio format handler for ogg/opus files. */
+
#include <ogg/ogg.h>
#include <regex.h>
#include "string.h"
#include "opus_common.h"
#include "ogg_afh_common.h"
+
+static const char * const opus_suffixes[] = {"opus", NULL};
+
+#define OPUS_COMMENT_HEADER "OpusTags"
+
+static bool copy_if_tag_type(const char *tag, int taglen, const char *type,
+ char **p)
+{
+ char *q = key_value_copy(tag, taglen, type);
+ if (!q)
+ return false;
+ free(*p);
+ *p = q;
+ return true;
+}
+
+static int opus_get_comments(char *comments, int length,
+ struct taginfo *tags)
+{
+ char *p = comments, *end = comments + length;
+ int i;
+ uint32_t val, ntags;
+
+ /* min size of a opus header is 16 bytes */
+ if (length < 16)
+ return -E_OPUS_COMMENT;
+ if (memcmp(p, OPUS_COMMENT_HEADER, strlen(OPUS_COMMENT_HEADER)) != 0)
+ return -E_OPUS_COMMENT;
+ p += 8;
+ val = read_u32(p);
+ p += 4;
+ if (p + val > end)
+ return -E_OPUS_COMMENT;
+ tags->comment = safe_strdup(p, val);
+ p += val;
+ ntags = read_u32(p);
+ p += 4;
+ if (p + ntags * 4 > end)
+ return -E_OPUS_COMMENT;
+ PARA_INFO_LOG("found %u tag(s)\n", ntags);
+ for (i = 0; i < ntags; i++, p += val) {
+ char *tag;
+
+ if (p + 4 > end)
+ return -E_OPUS_COMMENT;
+ val = read_u32(p);
+ p += 4;
+ if (p + val > end)
+ return -E_OPUS_COMMENT;
+ if (copy_if_tag_type(p, val, "author", &tags->artist))
+ continue;
+ if (copy_if_tag_type(p, val, "artist", &tags->artist))
+ continue;
+ if (copy_if_tag_type(p, val, "title", &tags->title))
+ continue;
+ if (copy_if_tag_type(p, val, "album", &tags->album))
+ continue;
+ if (copy_if_tag_type(p, val, "year", &tags->year))
+ continue;
+ if (copy_if_tag_type(p, val, "comment", &tags->comment))
+ continue;
+ tag = safe_strdup(p, val);
+ PARA_NOTICE_LOG("unrecognized tag: %s\n", tag);
+ free(tag);
+ }
+ return 1;
+}
+
+/*
+ * Ogg/Opus has two mandatory header packets:
+ *
+ * 1. ID header (identifies the stream as Opus). Dedicated "BOS" ogg page.
+ * 2. Comment header (metadata). May span multiple pages.
+ *
+ * See doc/draft-ietf-codec-oggopus.xml in the opus source tree for details.
+ */
+static int opus_packet_callback(ogg_packet *packet, int packet_num,
+ __a_unused int serial, struct afh_info *afhi,
+ void *private_data)
+{
+ int ret;
+ struct opus_header *oh = private_data;
+
+ if (packet_num == 0) {
+ ret = opus_parse_header((char *)packet->packet, packet->bytes, oh);
+ if (ret < 0)
+ return ret;
+ afhi->channels = oh->channels;
+ afhi->techinfo = make_message(
+ "header version %d, input sample rate: %" PRIu32 "Hz",
+ oh->version, oh->input_sample_rate);
+ /*
+ * The input sample rate is irrelevant for afhi->frequency as
+ * we always decode to 48kHz.
+ */
+ afhi->frequency = 48000;
+ return 1;
+ }
+ if (packet_num == 1) {
+ ret = opus_get_comments((char *)packet->packet, packet->bytes,
+ &afhi->tags);
+ if (ret < 0)
+ return ret;
+ return 0; /* header complete */
+ }
+ /* never reached */
+ assert(0);
+}
+
+static int opus_get_file_info(char *map, size_t numbytes, __a_unused int fd,
+ struct afh_info *afhi)
+{
+ int ret, ms;
+ struct opus_header oh = {.version = 0};
+
+ struct oac_callback_info opus_callback_info = {
+ .packet_callback = opus_packet_callback,
+ .private_data = &oh,
+ };
+ ret = oac_get_file_info(map, numbytes, afhi, &opus_callback_info);
+ if (ret < 0)
+ return ret;
+ ret = (afhi->chunk_table[afhi->chunks_total] - afhi->chunk_table[0]) * 8; /* bits */
+ ms = tv2ms(&afhi->chunk_tv) * afhi->chunks_total;
+ afhi->bitrate = ret / ms;
+ return 1;
+}
+
+static size_t opus_make_meta_packet(struct taginfo *tags, char **result)
+{
+ size_t sz;
+ char *buf, *p;
+ size_t comment_len = strlen(tags->comment),
+ artist_len = strlen(tags->artist),
+ title_len = strlen(tags->title),
+ album_len = strlen(tags->album),
+ year_len = strlen(tags->year);
+ uint32_t comment_sz = comment_len,
+ artist_sz = artist_len + strlen("artist="),
+ title_sz = title_len + strlen("title="),
+ album_sz = album_len + strlen("album="),
+ year_sz = year_len + strlen("year=");
+ uint32_t num_tags;
+
+ sz = strlen(OPUS_COMMENT_HEADER)
+ + 4 /* comment length (always present) */
+ + comment_sz
+ + 4; /* number of tags */
+ num_tags = 0;
+ if (artist_len) {
+ num_tags++;
+ sz += 4 + artist_sz;
+ }
+ if (title_len) {
+ num_tags++;
+ sz += 4 + title_sz;
+ }
+ if (album_len) {
+ num_tags++;
+ sz += 4 + album_sz;
+ }
+ if (year_len) {
+ num_tags++;
+ sz += 4 + year_sz;
+ }
+ PARA_DEBUG_LOG("meta packet size: %zu bytes\n", sz);
+ /* terminating zero byte for the last sprintf() */
+ buf = p = para_malloc(sz + 1);
+ memcpy(p, OPUS_COMMENT_HEADER, strlen(OPUS_COMMENT_HEADER));
+ p += strlen(OPUS_COMMENT_HEADER);
+ write_u32(p, comment_sz);
+ p += 4;
+ strcpy(p, tags->comment);
+ p += comment_sz;
+ write_u32(p, num_tags);
+ p += 4;
+ if (artist_len) {
+ write_u32(p, artist_sz);
+ p += 4;
+ sprintf(p, "artist=%s", tags->artist);
+ p += artist_sz;
+ }
+ if (title_len) {
+ write_u32(p, title_sz);
+ p += 4;
+ sprintf(p, "title=%s", tags->title);
+ p += title_sz;
+ }
+ if (album_len) {
+ write_u32(p, album_sz);
+ p += 4;
+ sprintf(p, "album=%s", tags->album);
+ p += album_sz;
+ }
+ if (year_len) {
+ write_u32(p, year_sz);
+ p += 4;
+ sprintf(p, "year=%s", tags->year);
+ p += year_sz;
+ }
+ assert(p == buf + sz);
+ *result = buf;
+ return sz;
+}
+
+static int opus_rewrite_tags(const char *map, size_t mapsize,
+ struct taginfo *tags, int output_fd,
+ __a_unused const char *filename)
+{
+ char *meta_packet;
+ size_t meta_sz;
+ int ret;
+
+ meta_sz = opus_make_meta_packet(tags, &meta_packet);
+ ret = oac_rewrite_tags(map, mapsize, output_fd, meta_packet, meta_sz);
+ free(meta_packet);
+ return ret;
+}
+
+/*
+ * See doc/draft-ietf-codec-oggopus.xml in the opus source tree for details
+ * about the format of the comment header.
+ */
+static int opus_get_header_callback(ogg_packet *packet, int packet_num,
+ int serial, __a_unused struct afh_info *afhi, void *private_data)
+{
+ struct oac_custom_header *h = private_data;
+ int ret;
+ static unsigned char dummy_tags[] = { /* a minimal comment header */
+ 'O', 'p', 'u', 's', 'T', 'a', 'g', 's',
+ 0x06, 0x00, 0x00, 0x00, /* vendor string length */
+ 'd', 'u', 'm', 'm', 'y', '\0', /* vendor string */
+ 0x00, 0x00, 0x00, 0x00, /* user comment list length */
+ };
+ ogg_packet replacement;
+
+ if (packet_num == 0) {
+ oac_custom_header_init(serial, h);
+ ret = oac_custom_header_append(packet, h);
+ if (ret < 0)
+ return ret;
+ oac_custom_header_flush(h);
+ return 1;
+ }
+ assert(packet_num == 1);
+ PARA_INFO_LOG("replacing metadata packet\n");
+ replacement = *packet;
+ replacement.packet = dummy_tags;
+ replacement.bytes = sizeof(dummy_tags);
+ ret = oac_custom_header_append(&replacement, h);
+ if (ret < 0)
+ return ret;
+ oac_custom_header_flush(h);
+ return 0;
+}
+
+static void opus_get_header(void *map, size_t mapsize, char **buf,
+ size_t *len)
+{
+ int ret;
+ struct oac_custom_header *h = oac_custom_header_new();
+ struct oac_callback_info cb = {
+ .packet_callback = opus_get_header_callback,
+ .private_data = h,
+ };
+
+ ret = oac_get_file_info(map, mapsize, NULL, &cb);
+ *len = oac_custom_header_get(buf, h);
+ if (ret < 0) {
+ PARA_ERROR_LOG("could not create custom header: %s\n",
+ para_strerror(-ret));
+ free(*buf);
+ *buf = NULL;
+ *len = 0;
+ } else
+ PARA_INFO_LOG("created %zu byte ogg/opus header\n", *len);
+}
+
/**
* The init function of the ogg/opus audio format handler.
*
*/
void opus_afh_init(struct audio_format_handler *afh)
{
-
+ afh->get_file_info = opus_get_file_info,
+ afh->get_header = opus_get_header;
+ afh->suffixes = opus_suffixes;
+ afh->rewrite_tags = opus_rewrite_tags;
}
projects / paraslash.git / blobdiff