ogg_afh.c

   1 /*
   2  * Copyright (C) 2004 Andre Noll <maan@tuebingen.mpg.de>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file ogg_afh.c Audio format handler for ogg/vorbis files. */
   8
   9 #include <vorbis/codec.h>
  10 #include <regex.h>
  11
  12 #include "para.h"
  13 #include "afh.h"
  14 #include "error.h"
  15 #include "string.h"
  16 #include "ogg_afh_common.h"
  17
  18 struct private_vorbis_data {
  19         vorbis_info vi;
  20         vorbis_comment vc;
  21 };
  22
  23 /*
  24  * Vorbis uses three header packets, all of which are required: the
  25  * identification header, the comments header, and the setup header.
  26  *
  27  * The identification header identifies the bitstream as Vorbis. It contains
  28  * the Vorbis version and simple audio characteristics of the stream such as
  29  * sample rate and number of channels.
  30  *
  31  * The comment header includes user text comments (tags) and a vendor string
  32  * for the application/library that produced the bitstream.
  33  *
  34  * The setup header includes extensive CODEC setup information as well as the
  35  * complete VQ and Huffman codebooks needed for decoding.
  36  */
  37 static int vorbis_packet_callback(ogg_packet *packet, int packet_num,
  38                 __a_unused int serial, struct afh_info *afhi, void *private_data)
  39 {
  40         struct private_vorbis_data *pvd = private_data;
  41
  42         if (vorbis_synthesis_headerin(&pvd->vi, &pvd->vc, packet) < 0)
  43                 return -E_VORBIS;
  44         if (packet_num == 0) {
  45                 if (pvd->vi.rate == 0)
  46                         return -E_VORBIS;
  47                 afhi->channels = pvd->vi.channels;
  48                 afhi->frequency = pvd->vi.rate;
  49                 afhi->bitrate = pvd->vi.bitrate_nominal / 1000;
  50                 PARA_DEBUG_LOG("channels: %i, sampling rate: %i, bitrate: %i\n",
  51                         afhi->channels, afhi->frequency, afhi->bitrate);
  52                 return 1;
  53         }
  54         if (packet_num == 1)
  55                 return 1; /* we also want to have packet #2 */
  56         afhi->tags.artist = para_strdup(vorbis_comment_query(&pvd->vc, "artist", 0));
  57         afhi->tags.title = para_strdup(vorbis_comment_query(&pvd->vc, "title", 0));
  58         afhi->tags.album = para_strdup(vorbis_comment_query(&pvd->vc, "album", 0));
  59         afhi->tags.year = para_strdup(vorbis_comment_query(&pvd->vc, "year", 0));
  60         afhi->tags.comment = para_strdup(vorbis_comment_query(&pvd->vc, "comment", 0));
  61         return 0;
  62 }
  63
  64 static int ogg_vorbis_get_file_info(char *map, size_t numbytes, __a_unused int fd,
  65                 struct afh_info *afhi)
  66 {
  67         int ret;
  68         struct private_vorbis_data pvd;
  69         struct oac_callback_info vorbis_callback_info = {
  70                 .packet_callback = vorbis_packet_callback,
  71                 .private_data = &pvd,
  72         };
  73
  74         vorbis_info_init(&pvd.vi);
  75         vorbis_comment_init(&pvd.vc);
  76         ret = oac_get_file_info(map, numbytes, afhi, &vorbis_callback_info);
  77         vorbis_info_clear(&pvd.vi);
  78         vorbis_comment_clear(&pvd.vc);
  79         return ret;
  80 }
  81
  82 static int vorbis_get_header_callback(ogg_packet *packet, int packet_num,
  83                 int serial, __a_unused struct afh_info *afhi, void *private_data)
  84 {
  85         int ret;
  86         struct oac_custom_header *h = private_data;
  87         static unsigned char dummy_packet[] = {
  88                 0x03,
  89                 'v', 'o', 'r', 'b', 'i', 's',
  90                 0x06, 0x00, 0x00, 0x00,
  91                 'd', 'u', 'm', 'm', 'y', '\0',
  92                 0x00, 0x00, 0x00, 0x00, /* no comment :) */
  93                 0xff /* framing bit */
  94         };
  95
  96         PARA_DEBUG_LOG("processing ogg packet #%d\n", packet_num);
  97         if (packet_num == 0) {
  98                 oac_custom_header_init(serial, h);
  99                 ret = oac_custom_header_append(packet, h);
 100                 if (ret < 0)
 101                         return ret;
 102                 oac_custom_header_flush(h);
 103                 return 1;
 104         }
 105         if (packet_num == 1) {
 106                 ogg_packet replacement = *packet;
 107                 PARA_INFO_LOG("replacing metadata packet\n");
 108                 replacement.packet = dummy_packet;
 109                 replacement.bytes = sizeof(dummy_packet);
 110                 ret = oac_custom_header_append(&replacement, h);
 111                 return ret < 0? ret : 1;
 112         }
 113         assert(packet_num == 2);
 114         ret = oac_custom_header_append(packet, h);
 115         if (ret < 0)
 116                 return ret;
 117         oac_custom_header_flush(h);
 118         return 0;
 119 }
 120
 121 static void vorbis_get_header(void *map, size_t mapsize, char **buf,
 122                 size_t *len)
 123 {
 124         int ret;
 125         struct oac_custom_header *h = oac_custom_header_new();
 126         struct oac_callback_info cb = {
 127                 .packet_callback = vorbis_get_header_callback,
 128                 .private_data = h,
 129         };
 130
 131         ret = oac_get_file_info(map, mapsize, NULL, &cb);
 132         *len = oac_custom_header_get(buf, h);
 133         if (ret < 0) {
 134                 PARA_ERROR_LOG("could not create ogg/vorbis header: %s\n",
 135                         para_strerror(-ret));
 136                 free(*buf);
 137                 *buf = NULL;
 138                 *len = 0;
 139         } else
 140                 PARA_INFO_LOG("created %zu byte ogg vorbis header\n", *len);
 141 }
 142
 143 static int vorbis_make_meta_packet(struct taginfo *tags, ogg_packet *result)
 144 {
 145         vorbis_comment vc;
 146         int ret;
 147
 148         vorbis_comment_init(&vc);
 149         vorbis_comment_add_tag(&vc, "artist", tags->artist);
 150         vorbis_comment_add_tag(&vc, "title", tags->title);
 151         vorbis_comment_add_tag(&vc, "album", tags->album);
 152         vorbis_comment_add_tag(&vc, "year", tags->year);
 153         vorbis_comment_add_tag(&vc, "comment", tags->comment);
 154         ret = vorbis_commentheader_out(&vc, result);
 155         vorbis_comment_clear(&vc);
 156         if (ret != 0)
 157                 return -E_VORBIS_COMMENTHEADER;
 158         return 1;
 159 }
 160
 161 static int vorbis_rewrite_tags(const char *map, size_t mapsize,
 162                 struct taginfo *tags, int output_fd,
 163                 __a_unused const char *filename)
 164 {
 165         int ret;
 166         ogg_packet packet;
 167
 168         ret = vorbis_make_meta_packet(tags, &packet);
 169         if (ret < 0)
 170                 return ret;
 171         ret = oac_rewrite_tags(map, mapsize, output_fd, (char *)packet.packet,
 172                 packet.bytes);
 173         free(packet.packet);
 174         return ret;
 175 }
 176
 177 static const char * const ogg_suffixes[] = {"ogg", NULL};
 178
 179 /**
 180  * The init function of the ogg vorbis audio format handler.
 181  *
 182  * \param afh Pointer to the struct to initialize.
 183  */
 184 void ogg_afh_init(struct audio_format_handler *afh)
 185 {
 186         afh->get_file_info = ogg_vorbis_get_file_info;
 187         afh->get_header = vorbis_get_header;
 188         afh->suffixes = ogg_suffixes;
 189         afh->rewrite_tags = vorbis_rewrite_tags;
 190 }