[deb_ffmpeg.git] / ffmpeg / libavformat / mp3enc.c

/*
 * MP3 muxer
 * Copyright (c) 2003 Fabrice Bellard
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * FFmpeg is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "avformat.h"
#include "avio_internal.h"
#include "id3v1.h"
#include "id3v2.h"
#include "rawenc.h"
#include "libavutil/avstring.h"
#include "libavcodec/mpegaudio.h"
#include "libavcodec/mpegaudiodata.h"
#include "libavcodec/mpegaudiodecheader.h"
#include "libavutil/intreadwrite.h"
#include "libavutil/opt.h"
#include "libavutil/dict.h"
#include "libavutil/avassert.h"
#include "libavutil/crc.h"
#include "libavutil/mathematics.h"
#include "libavutil/replaygain.h"

static int id3v1_set_string(AVFormatContext *s, const char *key,
                            uint8_t *buf, int buf_size)
{
    AVDictionaryEntry *tag;
    if ((tag = av_dict_get(s->metadata, key, NULL, 0)))
        av_strlcpy(buf, tag->value, buf_size);
    return !!tag;
}

static int id3v1_create_tag(AVFormatContext *s, uint8_t *buf)
{
    AVDictionaryEntry *tag;
    int i, count = 0;

    memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
    buf[0] = 'T';
    buf[1] = 'A';
    buf[2] = 'G';
    /* we knowingly overspecify each tag length by one byte to compensate for the mandatory null byte added by av_strlcpy */
    count += id3v1_set_string(s, "TIT2",    buf +  3, 30 + 1);       //title
    count += id3v1_set_string(s, "TPE1",    buf + 33, 30 + 1);       //author|artist
    count += id3v1_set_string(s, "TALB",    buf + 63, 30 + 1);       //album
    count += id3v1_set_string(s, "TDRC",    buf + 93,  4 + 1);       //date
    count += id3v1_set_string(s, "comment", buf + 97, 30 + 1);
    if ((tag = av_dict_get(s->metadata, "TRCK", NULL, 0))) { //track
        buf[125] = 0;
        buf[126] = atoi(tag->value);
        count++;
    }
    buf[127] = 0xFF; /* default to unknown genre */
    if ((tag = av_dict_get(s->metadata, "TCON", NULL, 0))) { //genre
        for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
            if (!av_strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
                buf[127] = i;
                count++;
                break;
            }
        }
    }
    return count;
}

#define XING_NUM_BAGS 400
#define XING_TOC_SIZE 100
// size of the XING/LAME data, starting from the Xing tag
#define XING_SIZE 156

typedef struct MP3Context {
    const AVClass *class;
    ID3v2EncContext id3;
    int id3v2_version;
    int write_id3v1;
    int write_xing;

    /* xing header */
    // a buffer containing the whole XING/LAME frame
    uint8_t *xing_frame;
    int      xing_frame_size;

    AVCRC    audio_crc;     // CRC of the audio data
    uint32_t audio_size;    // total size of the audio data

    // offset of the XING/LAME frame in the file
    int64_t  xing_frame_offset;
    // offset of the XING/INFO tag in the frame
    int xing_offset;

    int32_t frames;
    int32_t size;
    uint32_t want;
    uint32_t seen;
    uint32_t pos;
    uint64_t bag[XING_NUM_BAGS];
    int initial_bitrate;
    int has_variable_bitrate;

    /* index of the audio stream */
    int audio_stream_idx;
    /* number of attached pictures we still need to write */
    int pics_to_write;

    /* audio packets are queued here until we get all the attached pictures */
    AVPacketList *queue, *queue_end;
} MP3Context;

static const uint8_t xing_offtbl[2][2] = {{32, 17}, {17, 9}};

/*
 * Write an empty XING header and initialize respective data.
 */
static int mp3_write_xing(AVFormatContext *s)
{
    MP3Context       *mp3 = s->priv_data;
    AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
    AVDictionaryEntry *enc = av_dict_get(s->streams[mp3->audio_stream_idx]->metadata, "encoder", NULL, 0);
    AVIOContext *dyn_ctx;
    int32_t        header;
    MPADecodeHeader  mpah;
    int srate_idx, i, channels;
    int bitrate_idx;
    int best_bitrate_idx = -1;
    int best_bitrate_error = INT_MAX;
    int ret;
    int ver = 0;
    int bytes_needed;

    if (!s->pb->seekable || !mp3->write_xing)
        return 0;

    for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
        const uint16_t base_freq = avpriv_mpa_freq_tab[i];

        if      (codec->sample_rate == base_freq)     ver = 0x3; // MPEG 1
        else if (codec->sample_rate == base_freq / 2) ver = 0x2; // MPEG 2
        else if (codec->sample_rate == base_freq / 4) ver = 0x0; // MPEG 2.5
        else continue;

        srate_idx = i;
        break;
    }
    if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {
        av_log(s, AV_LOG_WARNING, "Unsupported sample rate, not writing Xing header.\n");
        return -1;
    }

    switch (codec->channels) {
    case 1:  channels = MPA_MONO;                                          break;
    case 2:  channels = MPA_STEREO;                                        break;
    default: av_log(s, AV_LOG_WARNING, "Unsupported number of channels, "
                    "not writing Xing header.\n");
             return -1;
    }

    /* dummy MPEG audio header */
    header  =  0xffU                                 << 24; // sync
    header |= (0x7 << 5 | ver << 3 | 0x1 << 1 | 0x1) << 16; // sync/audio-version/layer 3/no crc*/
    header |= (srate_idx << 2) << 8;
    header |= channels << 6;

    for (bitrate_idx = 1; bitrate_idx < 15; bitrate_idx++) {
        int bit_rate = 1000 * avpriv_mpa_bitrate_tab[ver != 3][3 - 1][bitrate_idx];
        int error    = FFABS(bit_rate - codec->bit_rate);

        if (error < best_bitrate_error) {
            best_bitrate_error = error;
            best_bitrate_idx   = bitrate_idx;
        }
    }
    av_assert0(best_bitrate_idx >= 0);

    for (bitrate_idx = best_bitrate_idx; ; bitrate_idx++) {
        int32_t mask = bitrate_idx << (4 + 8);
        if (15 == bitrate_idx)
            return -1;
        header |= mask;

        avpriv_mpegaudio_decode_header(&mpah, header);
        mp3->xing_offset = xing_offtbl[mpah.lsf == 1][mpah.nb_channels == 1] + 4;
        bytes_needed     = mp3->xing_offset + XING_SIZE;

        if (bytes_needed <= mpah.frame_size)
            break;

        header &= ~mask;
    }

    ret = avio_open_dyn_buf(&dyn_ctx);
    if (ret < 0)
        return ret;

    avio_wb32(dyn_ctx, header);

    ffio_fill(dyn_ctx, 0, mp3->xing_offset - 4);
    ffio_wfourcc(dyn_ctx, "Xing");
    avio_wb32(dyn_ctx, 0x01 | 0x02 | 0x04 | 0x08);  // frames / size / TOC / vbr scale

    mp3->size = mpah.frame_size;
    mp3->want=1;
    mp3->seen=0;
    mp3->pos=0;

    avio_wb32(dyn_ctx, 0);  // frames
    avio_wb32(dyn_ctx, 0);  // size

    // TOC
    for (i = 0; i < XING_TOC_SIZE; i++)
        avio_w8(dyn_ctx, (uint8_t)(255 * i / XING_TOC_SIZE));

    // vbr quality
    // we write it, because some (broken) tools always expect it to be present
    avio_wb32(dyn_ctx, 0);

    // encoder short version string
    if (enc) {
        uint8_t encoder_str[9] = { 0 };
        if (   strlen(enc->value) > sizeof(encoder_str)
            && !strcmp("Lavc libmp3lame", enc->value)) {
            memcpy(encoder_str, "Lavf lame", 9);
        } else
            memcpy(encoder_str, enc->value, FFMIN(strlen(enc->value), sizeof(encoder_str)));

        avio_write(dyn_ctx, encoder_str, sizeof(encoder_str));
    } else
        avio_write(dyn_ctx, "Lavf\0\0\0\0\0", 9);

    avio_w8(dyn_ctx, 0);      // tag revision 0 / unknown vbr method
    avio_w8(dyn_ctx, 0);      // unknown lowpass filter value
    ffio_fill(dyn_ctx, 0, 8); // empty replaygain fields
    avio_w8(dyn_ctx, 0);      // unknown encoding flags
    avio_w8(dyn_ctx, 0);      // unknown abr/minimal bitrate

    // encoder delay
    if (codec->initial_padding - 528 - 1 >= 1 << 12) {
        av_log(s, AV_LOG_WARNING, "Too many samples of initial padding.\n");
    }
    avio_wb24(dyn_ctx, FFMAX(codec->initial_padding - 528 - 1, 0)<<12);

    avio_w8(dyn_ctx,   0); // misc
    avio_w8(dyn_ctx,   0); // mp3gain
    avio_wb16(dyn_ctx, 0); // preset

    // audio length and CRCs (will be updated later)
    avio_wb32(dyn_ctx, 0); // music length
    avio_wb16(dyn_ctx, 0); // music crc
    avio_wb16(dyn_ctx, 0); // tag crc

    ffio_fill(dyn_ctx, 0, mpah.frame_size - bytes_needed);

    mp3->xing_frame_size   = avio_close_dyn_buf(dyn_ctx, &mp3->xing_frame);
    mp3->xing_frame_offset = avio_tell(s->pb);
    avio_write(s->pb, mp3->xing_frame, mp3->xing_frame_size);

    mp3->audio_size = mp3->xing_frame_size;

    return 0;
}

/*
 * Add a frame to XING data.
 * Following lame's "VbrTag.c".
 */
static void mp3_xing_add_frame(MP3Context *mp3, AVPacket *pkt)
{
    int i;

    mp3->frames++;
    mp3->seen++;
    mp3->size += pkt->size;

    if (mp3->want == mp3->seen) {
        mp3->bag[mp3->pos] = mp3->size;

        if (XING_NUM_BAGS == ++mp3->pos) {
            /* shrink table to half size by throwing away each second bag. */
            for (i = 1; i < XING_NUM_BAGS; i += 2)
                mp3->bag[i >> 1] = mp3->bag[i];

            /* double wanted amount per bag. */
            mp3->want *= 2;
            /* adjust current position to half of table size. */
            mp3->pos = XING_NUM_BAGS / 2;
        }

        mp3->seen = 0;
    }
}

static int mp3_write_audio_packet(AVFormatContext *s, AVPacket *pkt)
{
    MP3Context  *mp3 = s->priv_data;

    if (pkt->data && pkt->size >= 4) {
        MPADecodeHeader mpah;
        int av_unused base;
        uint32_t h;

        h = AV_RB32(pkt->data);
        if (ff_mpa_check_header(h) == 0) {
            avpriv_mpegaudio_decode_header(&mpah, h);
            if (!mp3->initial_bitrate)
                mp3->initial_bitrate = mpah.bit_rate;
            if ((mpah.bit_rate == 0) || (mp3->initial_bitrate != mpah.bit_rate))
                mp3->has_variable_bitrate = 1;
        } else {
            av_log(s, AV_LOG_WARNING, "Audio packet of size %d (starting with %08X...) "
                   "is invalid, writing it anyway.\n", pkt->size, h);
        }

#ifdef FILTER_VBR_HEADERS
        /* filter out XING and INFO headers. */
        base = 4 + xing_offtbl[mpah.lsf == 1][mpah.nb_channels == 1];

        if (base + 4 <= pkt->size) {
            uint32_t v = AV_RB32(pkt->data + base);

            if (MKBETAG('X','i','n','g') == v || MKBETAG('I','n','f','o') == v)
                return 0;
        }

        /* filter out VBRI headers. */
        base = 4 + 32;

        if (base + 4 <= pkt->size && MKBETAG('V','B','R','I') == AV_RB32(pkt->data + base))
            return 0;
#endif

        if (mp3->xing_offset) {
            mp3_xing_add_frame(mp3, pkt);
            mp3->audio_size += pkt->size;
            mp3->audio_crc   = av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE),
                                      mp3->audio_crc, pkt->data, pkt->size);
        }
    }

    return ff_raw_write_packet(s, pkt);
}

static int mp3_queue_flush(AVFormatContext *s)
{
    MP3Context *mp3 = s->priv_data;
    AVPacketList *pktl;
    int ret = 0, write = 1;

    ff_id3v2_finish(&mp3->id3, s->pb, s->metadata_header_padding);
    mp3_write_xing(s);

    while ((pktl = mp3->queue)) {
        if (write && (ret = mp3_write_audio_packet(s, &pktl->pkt)) < 0)
            write = 0;
        av_free_packet(&pktl->pkt);
        mp3->queue = pktl->next;
        av_freep(&pktl);
    }
    mp3->queue_end = NULL;
    return ret;
}

static void mp3_update_xing(AVFormatContext *s)
{
    MP3Context  *mp3 = s->priv_data;
    AVReplayGain *rg;
    uint16_t tag_crc;
    uint8_t *toc;
    int i, rg_size;

    /* replace "Xing" identification string with "Info" for CBR files. */
    if (!mp3->has_variable_bitrate)
        AV_WL32(mp3->xing_frame + mp3->xing_offset, MKTAG('I', 'n', 'f', 'o'));

    AV_WB32(mp3->xing_frame + mp3->xing_offset + 8,  mp3->frames);
    AV_WB32(mp3->xing_frame + mp3->xing_offset + 12, mp3->size);

    toc    = mp3->xing_frame + mp3->xing_offset + 16;
    toc[0] = 0;  // first toc entry has to be zero.
    for (i = 1; i < XING_TOC_SIZE; ++i) {
        int j = i * mp3->pos / XING_TOC_SIZE;
        int seek_point = 256LL * mp3->bag[j] / mp3->size;
        toc[i] = FFMIN(seek_point, 255);
    }

    /* write replaygain */
    rg = (AVReplayGain*)av_stream_get_side_data(s->streams[0], AV_PKT_DATA_REPLAYGAIN,
                                                &rg_size);
    if (rg && rg_size >= sizeof(*rg)) {
        uint16_t val;

        AV_WB32(mp3->xing_frame + mp3->xing_offset + 131,
                av_rescale(rg->track_peak, 1 << 23, 100000));

        if (rg->track_gain != INT32_MIN) {
            val  = FFABS(rg->track_gain / 10000) & ((1 << 9) - 1);
            val |= (rg->track_gain < 0) << 9;
            val |= 1 << 13;
            AV_WB16(mp3->xing_frame + mp3->xing_offset + 135, val);
        }

        if (rg->album_gain != INT32_MIN) {
            val  = FFABS(rg->album_gain / 10000) & ((1 << 9) - 1);
            val |= (rg->album_gain < 0) << 9;
            val |= 1 << 14;
            AV_WB16(mp3->xing_frame + mp3->xing_offset + 137, val);
        }
    }

    AV_WB32(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 8, mp3->audio_size);
    AV_WB16(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 4, mp3->audio_crc);

    tag_crc = av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), 0, mp3->xing_frame, 190);
    AV_WB16(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 2, tag_crc);

    avio_seek(s->pb,  mp3->xing_frame_offset, SEEK_SET);
    avio_write(s->pb, mp3->xing_frame, mp3->xing_frame_size);
    avio_seek(s->pb, 0, SEEK_END);
}

static int mp3_write_trailer(struct AVFormatContext *s)
{
    uint8_t buf[ID3v1_TAG_SIZE];
    MP3Context *mp3 = s->priv_data;

    if (mp3->pics_to_write) {
        av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
               "attached pictures.\n");
        mp3_queue_flush(s);
    }

    /* write the id3v1 tag */
    if (mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
        avio_write(s->pb, buf, ID3v1_TAG_SIZE);
    }

    if (mp3->xing_offset)
        mp3_update_xing(s);

    av_freep(&mp3->xing_frame);

    return 0;
}

static int query_codec(enum AVCodecID id, int std_compliance)
{
    const CodecMime *cm= ff_id3v2_mime_tags;
    while(cm->id != AV_CODEC_ID_NONE) {
        if(id == cm->id)
            return MKTAG('A', 'P', 'I', 'C');
        cm++;
    }
    return -1;
}

#if CONFIG_MP2_MUXER
AVOutputFormat ff_mp2_muxer = {
    .name              = "mp2",
    .long_name         = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
    .mime_type         = "audio/mpeg",
    .extensions        = "mp2,m2a,mpa",
    .audio_codec       = AV_CODEC_ID_MP2,
    .video_codec       = AV_CODEC_ID_NONE,
    .write_packet      = ff_raw_write_packet,
    .flags             = AVFMT_NOTIMESTAMPS,
};
#endif

#if CONFIG_MP3_MUXER

static const AVOption options[] = {
    { "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
      offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.i64 = 4}, 0, 4, AV_OPT_FLAG_ENCODING_PARAM},
    { "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
      offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
    { "write_xing",  "Write the Xing header containing file duration.",
      offsetof(MP3Context, write_xing),  AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
    { NULL },
};

static const AVClass mp3_muxer_class = {
    .class_name     = "MP3 muxer",
    .item_name      = av_default_item_name,
    .option         = options,
    .version        = LIBAVUTIL_VERSION_INT,
};

static int mp3_write_packet(AVFormatContext *s, AVPacket *pkt)
{
    MP3Context *mp3 = s->priv_data;

    if (pkt->stream_index == mp3->audio_stream_idx) {
        if (mp3->pics_to_write) {
            /* buffer audio packets until we get all the pictures */
            AVPacketList *pktl = av_mallocz(sizeof(*pktl));
            int ret;
            if (!pktl) {
                av_log(s, AV_LOG_WARNING, "Not enough memory to buffer audio. Skipping picture streams\n");
                mp3->pics_to_write = 0;
                mp3_queue_flush(s);
                return mp3_write_audio_packet(s, pkt);
            }

            ret = av_copy_packet(&pktl->pkt, pkt);
            if (ret < 0) {
                av_freep(&pktl);
                return ret;
            }

            if (mp3->queue_end)
                mp3->queue_end->next = pktl;
            else
                mp3->queue = pktl;
            mp3->queue_end = pktl;
        } else
            return mp3_write_audio_packet(s, pkt);
    } else {
        int ret;

        /* warn only once for each stream */
        if (s->streams[pkt->stream_index]->nb_frames == 1) {
            av_log(s, AV_LOG_WARNING, "Got more than one picture in stream %d,"
                   " ignoring.\n", pkt->stream_index);
        }
        if (!mp3->pics_to_write || s->streams[pkt->stream_index]->nb_frames >= 1)
            return 0;

        if ((ret = ff_id3v2_write_apic(s, &mp3->id3, pkt)) < 0)
            return ret;
        mp3->pics_to_write--;

        /* flush the buffered audio packets */
        if (!mp3->pics_to_write &&
            (ret = mp3_queue_flush(s)) < 0)
            return ret;
    }

    return 0;
}

/**
 * Write an ID3v2 header at beginning of stream
 */

static int mp3_write_header(struct AVFormatContext *s)
{
    MP3Context  *mp3 = s->priv_data;
    int ret, i;

    if (mp3->id3v2_version      &&
        mp3->id3v2_version != 3 &&
        mp3->id3v2_version != 4) {
        av_log(s, AV_LOG_ERROR, "Invalid ID3v2 version requested: %d. Only "
               "3, 4 or 0 (disabled) are allowed.\n", mp3->id3v2_version);
        return AVERROR(EINVAL);
    }

    /* check the streams -- we want exactly one audio and arbitrary number of
     * video (attached pictures) */
    mp3->audio_stream_idx = -1;
    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st = s->streams[i];
        if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
            if (mp3->audio_stream_idx >= 0 || st->codec->codec_id != AV_CODEC_ID_MP3) {
                av_log(s, AV_LOG_ERROR, "Invalid audio stream. Exactly one MP3 "
                       "audio stream is required.\n");
                return AVERROR(EINVAL);
            }
            mp3->audio_stream_idx = i;
        } else if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
            av_log(s, AV_LOG_ERROR, "Only audio streams and pictures are allowed in MP3.\n");
            return AVERROR(EINVAL);
        }
    }
    if (mp3->audio_stream_idx < 0) {
        av_log(s, AV_LOG_ERROR, "No audio stream present.\n");
        return AVERROR(EINVAL);
    }
    mp3->pics_to_write = s->nb_streams - 1;

    if (mp3->pics_to_write && !mp3->id3v2_version) {
        av_log(s, AV_LOG_ERROR, "Attached pictures were requested, but the "
               "ID3v2 header is disabled.\n");
        return AVERROR(EINVAL);
    }

    if (mp3->id3v2_version) {
        ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
        ret = ff_id3v2_write_metadata(s, &mp3->id3);
        if (ret < 0)
            return ret;
    }

    if (!mp3->pics_to_write) {
        if (mp3->id3v2_version)
            ff_id3v2_finish(&mp3->id3, s->pb, s->metadata_header_padding);
        mp3_write_xing(s);
    }

    return 0;
}

AVOutputFormat ff_mp3_muxer = {
    .name              = "mp3",
    .long_name         = NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
    .mime_type         = "audio/mpeg",
    .extensions        = "mp3",
    .priv_data_size    = sizeof(MP3Context),
    .audio_codec       = AV_CODEC_ID_MP3,
    .video_codec       = AV_CODEC_ID_PNG,
    .write_header      = mp3_write_header,
    .write_packet      = mp3_write_packet,
    .write_trailer     = mp3_write_trailer,
    .query_codec       = query_codec,
    .flags             = AVFMT_NOTIMESTAMPS,
    .priv_class        = &mp3_muxer_class,
};
#endif
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* MP3 muxer
	3	* Copyright (c) 2003 Fabrice Bellard
	4	*
	5	* This file is part of FFmpeg.
	6	*
	7	* FFmpeg is free software; you can redistribute it and/or
	8	* modify it under the terms of the GNU Lesser General Public
	9	* License as published by the Free Software Foundation; either
	10	* version 2.1 of the License, or (at your option) any later version.
	11	*
	12	* FFmpeg is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	15	* Lesser General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU Lesser General Public
	18	* License along with FFmpeg; if not, write to the Free Software
	19	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	20	*/
	21
	22	#include "avformat.h"
	23	#include "avio_internal.h"
	24	#include "id3v1.h"
	25	#include "id3v2.h"
	26	#include "rawenc.h"
	27	#include "libavutil/avstring.h"
	28	#include "libavcodec/mpegaudio.h"
	29	#include "libavcodec/mpegaudiodata.h"
	30	#include "libavcodec/mpegaudiodecheader.h"
	31	#include "libavutil/intreadwrite.h"
	32	#include "libavutil/opt.h"
	33	#include "libavutil/dict.h"
	34	#include "libavutil/avassert.h"
f6fa7814 DM	35	#include "libavutil/crc.h"
	36	#include "libavutil/mathematics.h"
	37	#include "libavutil/replaygain.h"
2ba45a60 DM	38
	39	static int id3v1_set_string(AVFormatContext s, const char key,
	40	uint8_t *buf, int buf_size)
	41	{
	42	AVDictionaryEntry *tag;
	43	if ((tag = av_dict_get(s->metadata, key, NULL, 0)))
	44	av_strlcpy(buf, tag->value, buf_size);
	45	return !!tag;
	46	}
	47
	48	static int id3v1_create_tag(AVFormatContext s, uint8_t buf)
	49	{
	50	AVDictionaryEntry *tag;
	51	int i, count = 0;
	52
	53	memset(buf, 0, ID3v1_TAG_SIZE); /* fail safe */
	54	buf[0] = 'T';
	55	buf[1] = 'A';
	56	buf[2] = 'G';
	57	/* we knowingly overspecify each tag length by one byte to compensate for the mandatory null byte added by av_strlcpy */
	58	count += id3v1_set_string(s, "TIT2", buf + 3, 30 + 1); //title
	59	count += id3v1_set_string(s, "TPE1", buf + 33, 30 + 1); //author\|artist
	60	count += id3v1_set_string(s, "TALB", buf + 63, 30 + 1); //album
f6fa7814	61	count += id3v1_set_string(s, "TDRC", buf + 93, 4 + 1); //date
2ba45a60 DM	62	count += id3v1_set_string(s, "comment", buf + 97, 30 + 1);
	63	if ((tag = av_dict_get(s->metadata, "TRCK", NULL, 0))) { //track
	64	buf[125] = 0;
	65	buf[126] = atoi(tag->value);
	66	count++;
	67	}
	68	buf[127] = 0xFF; /* default to unknown genre */
	69	if ((tag = av_dict_get(s->metadata, "TCON", NULL, 0))) { //genre
	70	for(i = 0; i <= ID3v1_GENRE_MAX; i++) {
	71	if (!av_strcasecmp(tag->value, ff_id3v1_genre_str[i])) {
	72	buf[127] = i;
	73	count++;
	74	break;
	75	}
	76	}
	77	}
	78	return count;
	79	}
	80
	81	#define XING_NUM_BAGS 400
	82	#define XING_TOC_SIZE 100
f6fa7814 DM	83	// size of the XING/LAME data, starting from the Xing tag
f6fa7814 DM	84	#define XING_SIZE 156
2ba45a60 DM	85
	86	typedef struct MP3Context {
	87	const AVClass *class;
	88	ID3v2EncContext id3;
	89	int id3v2_version;
	90	int write_id3v1;
	91	int write_xing;
	92
	93	/* xing header */
f6fa7814 DM	94	// a buffer containing the whole XING/LAME frame
	95	uint8_t *xing_frame;
	96	int xing_frame_size;
	97
	98	AVCRC audio_crc; // CRC of the audio data
	99	uint32_t audio_size; // total size of the audio data
	100
	101	// offset of the XING/LAME frame in the file
	102	int64_t xing_frame_offset;
	103	// offset of the XING/INFO tag in the frame
	104	int xing_offset;
	105
2ba45a60 DM	106	int32_t frames;
	107	int32_t size;
	108	uint32_t want;
	109	uint32_t seen;
	110	uint32_t pos;
	111	uint64_t bag[XING_NUM_BAGS];
	112	int initial_bitrate;
	113	int has_variable_bitrate;
	114
	115	/* index of the audio stream */
	116	int audio_stream_idx;
	117	/* number of attached pictures we still need to write */
	118	int pics_to_write;
	119
	120	/* audio packets are queued here until we get all the attached pictures */
	121	AVPacketList queue, queue_end;
	122	} MP3Context;
	123
	124	static const uint8_t xing_offtbl[2][2] = {{32, 17}, {17, 9}};
	125
	126	/*
	127	* Write an empty XING header and initialize respective data.
	128	*/
	129	static int mp3_write_xing(AVFormatContext *s)
	130	{
	131	MP3Context *mp3 = s->priv_data;
	132	AVCodecContext *codec = s->streams[mp3->audio_stream_idx]->codec;
f6fa7814 DM	133	AVDictionaryEntry *enc = av_dict_get(s->streams[mp3->audio_stream_idx]->metadata, "encoder", NULL, 0);
	134	AVIOContext *dyn_ctx;
	135	int32_t header;
2ba45a60 DM	136	MPADecodeHeader mpah;
	137	int srate_idx, i, channels;
	138	int bitrate_idx;
	139	int best_bitrate_idx = -1;
	140	int best_bitrate_error = INT_MAX;
f6fa7814	141	int ret;
2ba45a60 DM	142	int ver = 0;
2ba45a60 DM	143	int bytes_needed;
2ba45a60 DM	144
	145	if (!s->pb->seekable \|\| !mp3->write_xing)
	146	return 0;
	147
	148	for (i = 0; i < FF_ARRAY_ELEMS(avpriv_mpa_freq_tab); i++) {
	149	const uint16_t base_freq = avpriv_mpa_freq_tab[i];
	150
	151	if (codec->sample_rate == base_freq) ver = 0x3; // MPEG 1
	152	else if (codec->sample_rate == base_freq / 2) ver = 0x2; // MPEG 2
	153	else if (codec->sample_rate == base_freq / 4) ver = 0x0; // MPEG 2.5
	154	else continue;
	155
	156	srate_idx = i;
	157	break;
	158	}
	159	if (i == FF_ARRAY_ELEMS(avpriv_mpa_freq_tab)) {
	160	av_log(s, AV_LOG_WARNING, "Unsupported sample rate, not writing Xing header.\n");
	161	return -1;
	162	}
	163
	164	switch (codec->channels) {
	165	case 1: channels = MPA_MONO; break;
	166	case 2: channels = MPA_STEREO; break;
	167	default: av_log(s, AV_LOG_WARNING, "Unsupported number of channels, "
	168	"not writing Xing header.\n");
	169	return -1;
	170	}
	171
	172	/* dummy MPEG audio header */
	173	header = 0xffU << 24; // sync
	174	header \|= (0x7 << 5 \| ver << 3 \| 0x1 << 1 \| 0x1) << 16; // sync/audio-version/layer 3/no crc*/
	175	header \|= (srate_idx << 2) << 8;
	176	header \|= channels << 6;
	177
	178	for (bitrate_idx = 1; bitrate_idx < 15; bitrate_idx++) {
	179	int bit_rate = 1000 * avpriv_mpa_bitrate_tab[ver != 3][3 - 1][bitrate_idx];
	180	int error = FFABS(bit_rate - codec->bit_rate);
	181
	182	if (error < best_bitrate_error) {
	183	best_bitrate_error = error;
	184	best_bitrate_idx = bitrate_idx;
	185	}
	186	}
	187	av_assert0(best_bitrate_idx >= 0);
	188
	189	for (bitrate_idx = best_bitrate_idx; ; bitrate_idx++) {
	190	int32_t mask = bitrate_idx << (4 + 8);
	191	if (15 == bitrate_idx)
	192	return -1;
	193	header \|= mask;
	194
	195	avpriv_mpegaudio_decode_header(&mpah, header);
f6fa7814 DM	196	mp3->xing_offset = xing_offtbl[mpah.lsf == 1][mpah.nb_channels == 1] + 4;
f6fa7814 DM	197	bytes_needed = mp3->xing_offset + XING_SIZE;
2ba45a60 DM	198
	199	if (bytes_needed <= mpah.frame_size)
	200	break;
	201
	202	header &= ~mask;
	203	}
	204
f6fa7814 DM	205	ret = avio_open_dyn_buf(&dyn_ctx);
	206	if (ret < 0)
	207	return ret;
	208
	209	avio_wb32(dyn_ctx, header);
2ba45a60	210
f6fa7814 DM	211	ffio_fill(dyn_ctx, 0, mp3->xing_offset - 4);
	212	ffio_wfourcc(dyn_ctx, "Xing");
	213	avio_wb32(dyn_ctx, 0x01 \| 0x02 \| 0x04 \| 0x08); // frames / size / TOC / vbr scale
2ba45a60 DM	214
	215	mp3->size = mpah.frame_size;
	216	mp3->want=1;
	217	mp3->seen=0;
	218	mp3->pos=0;
	219
f6fa7814 DM	220	avio_wb32(dyn_ctx, 0); // frames
	221	avio_wb32(dyn_ctx, 0); // size
	222
	223	// TOC
	224	for (i = 0; i < XING_TOC_SIZE; i++)
	225	avio_w8(dyn_ctx, (uint8_t)(255 * i / XING_TOC_SIZE));
	226
	227	// vbr quality
	228	// we write it, because some (broken) tools always expect it to be present
	229	avio_wb32(dyn_ctx, 0);
	230
	231	// encoder short version string
	232	if (enc) {
	233	uint8_t encoder_str[9] = { 0 };
	234	if ( strlen(enc->value) > sizeof(encoder_str)
	235	&& !strcmp("Lavc libmp3lame", enc->value)) {
	236	memcpy(encoder_str, "Lavf lame", 9);
	237	} else
	238	memcpy(encoder_str, enc->value, FFMIN(strlen(enc->value), sizeof(encoder_str)));
	239
	240	avio_write(dyn_ctx, encoder_str, sizeof(encoder_str));
	241	} else
	242	avio_write(dyn_ctx, "Lavf\0\0\0\0\0", 9);
	243
	244	avio_w8(dyn_ctx, 0); // tag revision 0 / unknown vbr method
	245	avio_w8(dyn_ctx, 0); // unknown lowpass filter value
	246	ffio_fill(dyn_ctx, 0, 8); // empty replaygain fields
	247	avio_w8(dyn_ctx, 0); // unknown encoding flags
	248	avio_w8(dyn_ctx, 0); // unknown abr/minimal bitrate
	249
	250	// encoder delay
	251	if (codec->initial_padding - 528 - 1 >= 1 << 12) {
	252	av_log(s, AV_LOG_WARNING, "Too many samples of initial padding.\n");
	253	}
	254	avio_wb24(dyn_ctx, FFMAX(codec->initial_padding - 528 - 1, 0)<<12);
	255
	256	avio_w8(dyn_ctx, 0); // misc
	257	avio_w8(dyn_ctx, 0); // mp3gain
	258	avio_wb16(dyn_ctx, 0); // preset
	259
	260	// audio length and CRCs (will be updated later)
	261	avio_wb32(dyn_ctx, 0); // music length
	262	avio_wb16(dyn_ctx, 0); // music crc
	263	avio_wb16(dyn_ctx, 0); // tag crc
2ba45a60	264
f6fa7814	265	ffio_fill(dyn_ctx, 0, mpah.frame_size - bytes_needed);
2ba45a60	266
f6fa7814 DM	267	mp3->xing_frame_size = avio_close_dyn_buf(dyn_ctx, &mp3->xing_frame);
	268	mp3->xing_frame_offset = avio_tell(s->pb);
	269	avio_write(s->pb, mp3->xing_frame, mp3->xing_frame_size);
2ba45a60	270
f6fa7814	271	mp3->audio_size = mp3->xing_frame_size;
2ba45a60 DM	272
	273	return 0;
	274	}
	275
	276	/*
	277	* Add a frame to XING data.
	278	* Following lame's "VbrTag.c".
	279	*/
	280	static void mp3_xing_add_frame(MP3Context mp3, AVPacket pkt)
	281	{
	282	int i;
	283
	284	mp3->frames++;
	285	mp3->seen++;
	286	mp3->size += pkt->size;
	287
	288	if (mp3->want == mp3->seen) {
	289	mp3->bag[mp3->pos] = mp3->size;
	290
	291	if (XING_NUM_BAGS == ++mp3->pos) {
	292	/* shrink table to half size by throwing away each second bag. */
	293	for (i = 1; i < XING_NUM_BAGS; i += 2)
	294	mp3->bag[i >> 1] = mp3->bag[i];
	295
	296	/* double wanted amount per bag. */
	297	mp3->want *= 2;
	298	/* adjust current position to half of table size. */
	299	mp3->pos = XING_NUM_BAGS / 2;
	300	}
	301
	302	mp3->seen = 0;
	303	}
	304	}
	305
	306	static int mp3_write_audio_packet(AVFormatContext s, AVPacket pkt)
	307	{
	308	MP3Context *mp3 = s->priv_data;
	309
	310	if (pkt->data && pkt->size >= 4) {
	311	MPADecodeHeader mpah;
	312	int av_unused base;
	313	uint32_t h;
	314
	315	h = AV_RB32(pkt->data);
	316	if (ff_mpa_check_header(h) == 0) {
	317	avpriv_mpegaudio_decode_header(&mpah, h);
	318	if (!mp3->initial_bitrate)
	319	mp3->initial_bitrate = mpah.bit_rate;
	320	if ((mpah.bit_rate == 0) \|\| (mp3->initial_bitrate != mpah.bit_rate))
	321	mp3->has_variable_bitrate = 1;
	322	} else {
	323	av_log(s, AV_LOG_WARNING, "Audio packet of size %d (starting with %08X...) "
	324	"is invalid, writing it anyway.\n", pkt->size, h);
	325	}
	326
	327	#ifdef FILTER_VBR_HEADERS
	328	/* filter out XING and INFO headers. */
	329	base = 4 + xing_offtbl[mpah.lsf == 1][mpah.nb_channels == 1];
	330
	331	if (base + 4 <= pkt->size) {
	332	uint32_t v = AV_RB32(pkt->data + base);
	333
	334	if (MKBETAG('X','i','n','g') == v \|\| MKBETAG('I','n','f','o') == v)
	335	return 0;
336	}
337
338	/* filter out VBRI headers. */
339	base = 4 + 32;
340
341	if (base + 4 <= pkt->size && MKBETAG('V','B','R','I') == AV_RB32(pkt->data + base))
342	return 0;
343	#endif
344
f6fa7814	345	if (mp3->xing_offset) {
2ba45a60	346	mp3_xing_add_frame(mp3, pkt);
f6fa7814 DM	347	mp3->audio_size += pkt->size;
	348	mp3->audio_crc = av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE),
	349	mp3->audio_crc, pkt->data, pkt->size);
	350	}
2ba45a60 DM	351	}
	352
	353	return ff_raw_write_packet(s, pkt);
	354	}
	355
	356	static int mp3_queue_flush(AVFormatContext *s)
	357	{
	358	MP3Context *mp3 = s->priv_data;
	359	AVPacketList *pktl;
	360	int ret = 0, write = 1;
	361
	362	ff_id3v2_finish(&mp3->id3, s->pb, s->metadata_header_padding);
	363	mp3_write_xing(s);
	364
	365	while ((pktl = mp3->queue)) {
	366	if (write && (ret = mp3_write_audio_packet(s, &pktl->pkt)) < 0)
	367	write = 0;
	368	av_free_packet(&pktl->pkt);
	369	mp3->queue = pktl->next;
	370	av_freep(&pktl);
	371	}
	372	mp3->queue_end = NULL;
	373	return ret;
	374	}
	375
	376	static void mp3_update_xing(AVFormatContext *s)
	377	{
	378	MP3Context *mp3 = s->priv_data;
f6fa7814 DM	379	AVReplayGain *rg;
	380	uint16_t tag_crc;
	381	uint8_t *toc;
	382	int i, rg_size;
2ba45a60 DM	383
2ba45a60 DM	384	/* replace "Xing" identification string with "Info" for CBR files. */
f6fa7814 DM	385	if (!mp3->has_variable_bitrate)
f6fa7814 DM	386	AV_WL32(mp3->xing_frame + mp3->xing_offset, MKTAG('I', 'n', 'f', 'o'));
2ba45a60	387
f6fa7814 DM	388	AV_WB32(mp3->xing_frame + mp3->xing_offset + 8, mp3->frames);
f6fa7814 DM	389	AV_WB32(mp3->xing_frame + mp3->xing_offset + 12, mp3->size);
2ba45a60	390
f6fa7814 DM	391	toc = mp3->xing_frame + mp3->xing_offset + 16;
f6fa7814 DM	392	toc[0] = 0; // first toc entry has to be zero.
2ba45a60 DM	393	for (i = 1; i < XING_TOC_SIZE; ++i) {
	394	int j = i * mp3->pos / XING_TOC_SIZE;
	395	int seek_point = 256LL * mp3->bag[j] / mp3->size;
f6fa7814	396	toc[i] = FFMIN(seek_point, 255);
2ba45a60 DM	397	}
2ba45a60 DM	398
f6fa7814 DM	399	/* write replaygain */
	400	rg = (AVReplayGain*)av_stream_get_side_data(s->streams[0], AV_PKT_DATA_REPLAYGAIN,
	401	&rg_size);
	402	if (rg && rg_size >= sizeof(*rg)) {
	403	uint16_t val;
	404
	405	AV_WB32(mp3->xing_frame + mp3->xing_offset + 131,
	406	av_rescale(rg->track_peak, 1 << 23, 100000));
	407
	408	if (rg->track_gain != INT32_MIN) {
	409	val = FFABS(rg->track_gain / 10000) & ((1 << 9) - 1);
	410	val \|= (rg->track_gain < 0) << 9;
	411	val \|= 1 << 13;
	412	AV_WB16(mp3->xing_frame + mp3->xing_offset + 135, val);
	413	}
	414
	415	if (rg->album_gain != INT32_MIN) {
	416	val = FFABS(rg->album_gain / 10000) & ((1 << 9) - 1);
	417	val \|= (rg->album_gain < 0) << 9;
	418	val \|= 1 << 14;
	419	AV_WB16(mp3->xing_frame + mp3->xing_offset + 137, val);
	420	}
	421	}
	422
	423	AV_WB32(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 8, mp3->audio_size);
	424	AV_WB16(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 4, mp3->audio_crc);
	425
	426	tag_crc = av_crc(av_crc_get_table(AV_CRC_16_ANSI_LE), 0, mp3->xing_frame, 190);
	427	AV_WB16(mp3->xing_frame + mp3->xing_offset + XING_SIZE - 2, tag_crc);
	428
	429	avio_seek(s->pb, mp3->xing_frame_offset, SEEK_SET);
	430	avio_write(s->pb, mp3->xing_frame, mp3->xing_frame_size);
2ba45a60 DM	431	avio_seek(s->pb, 0, SEEK_END);
	432	}
	433
	434	static int mp3_write_trailer(struct AVFormatContext *s)
	435	{
	436	uint8_t buf[ID3v1_TAG_SIZE];
	437	MP3Context *mp3 = s->priv_data;
	438
	439	if (mp3->pics_to_write) {
	440	av_log(s, AV_LOG_WARNING, "No packets were sent for some of the "
	441	"attached pictures.\n");
	442	mp3_queue_flush(s);
	443	}
	444
	445	/* write the id3v1 tag */
	446	if (mp3->write_id3v1 && id3v1_create_tag(s, buf) > 0) {
	447	avio_write(s->pb, buf, ID3v1_TAG_SIZE);
	448	}
	449
	450	if (mp3->xing_offset)
	451	mp3_update_xing(s);
	452
f6fa7814 DM	453	av_freep(&mp3->xing_frame);
f6fa7814 DM	454
2ba45a60 DM	455	return 0;
	456	}
	457
	458	static int query_codec(enum AVCodecID id, int std_compliance)
	459	{
	460	const CodecMime *cm= ff_id3v2_mime_tags;
	461	while(cm->id != AV_CODEC_ID_NONE) {
	462	if(id == cm->id)
	463	return MKTAG('A', 'P', 'I', 'C');
	464	cm++;
	465	}
	466	return -1;
	467	}
	468
	469	#if CONFIG_MP2_MUXER
	470	AVOutputFormat ff_mp2_muxer = {
	471	.name = "mp2",
	472	.long_name = NULL_IF_CONFIG_SMALL("MP2 (MPEG audio layer 2)"),
	473	.mime_type = "audio/mpeg",
	474	.extensions = "mp2,m2a,mpa",
	475	.audio_codec = AV_CODEC_ID_MP2,
	476	.video_codec = AV_CODEC_ID_NONE,
	477	.write_packet = ff_raw_write_packet,
	478	.flags = AVFMT_NOTIMESTAMPS,
	479	};
	480	#endif
	481
	482	#if CONFIG_MP3_MUXER
	483
	484	static const AVOption options[] = {
	485	{ "id3v2_version", "Select ID3v2 version to write. Currently 3 and 4 are supported.",
	486	offsetof(MP3Context, id3v2_version), AV_OPT_TYPE_INT, {.i64 = 4}, 0, 4, AV_OPT_FLAG_ENCODING_PARAM},
	487	{ "write_id3v1", "Enable ID3v1 writing. ID3v1 tags are written in UTF-8 which may not be supported by most software.",
	488	offsetof(MP3Context, write_id3v1), AV_OPT_TYPE_INT, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
	489	{ "write_xing", "Write the Xing header containing file duration.",
	490	offsetof(MP3Context, write_xing), AV_OPT_TYPE_INT, {.i64 = 1}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
	491	{ NULL },
	492	};
	493
	494	static const AVClass mp3_muxer_class = {
	495	.class_name = "MP3 muxer",
	496	.item_name = av_default_item_name,
	497	.option = options,
	498	.version = LIBAVUTIL_VERSION_INT,
	499	};
	500
	501	static int mp3_write_packet(AVFormatContext s, AVPacket pkt)
	502	{
	503	MP3Context *mp3 = s->priv_data;
	504
	505	if (pkt->stream_index == mp3->audio_stream_idx) {
	506	if (mp3->pics_to_write) {
	507	/* buffer audio packets until we get all the pictures */
	508	AVPacketList pktl = av_mallocz(sizeof(pktl));
	509	int ret;
	510	if (!pktl) {
	511	av_log(s, AV_LOG_WARNING, "Not enough memory to buffer audio. Skipping picture streams\n");
	512	mp3->pics_to_write = 0;
	513	mp3_queue_flush(s);
	514	return mp3_write_audio_packet(s, pkt);
	515	}
	516
	517	ret = av_copy_packet(&pktl->pkt, pkt);
	518	if (ret < 0) {
519	av_freep(&pktl);
520	return ret;
521	}
522
523	if (mp3->queue_end)
524	mp3->queue_end->next = pktl;
525	else
526	mp3->queue = pktl;
527	mp3->queue_end = pktl;
528	} else
529	return mp3_write_audio_packet(s, pkt);
530	} else {
531	int ret;
532
533	/* warn only once for each stream */
534	if (s->streams[pkt->stream_index]->nb_frames == 1) {
535	av_log(s, AV_LOG_WARNING, "Got more than one picture in stream %d,"
536	" ignoring.\n", pkt->stream_index);
537	}
538	if (!mp3->pics_to_write \|\| s->streams[pkt->stream_index]->nb_frames >= 1)
539	return 0;
540
541	if ((ret = ff_id3v2_write_apic(s, &mp3->id3, pkt)) < 0)
542	return ret;
543	mp3->pics_to_write--;
544
545	/* flush the buffered audio packets */
546	if (!mp3->pics_to_write &&
547	(ret = mp3_queue_flush(s)) < 0)
548	return ret;
549	}
550
551	return 0;
552	}
553
554	/**
555	* Write an ID3v2 header at beginning of stream
556	*/
557
558	static int mp3_write_header(struct AVFormatContext *s)
559	{
560	MP3Context *mp3 = s->priv_data;
561	int ret, i;
562
563	if (mp3->id3v2_version &&
564	mp3->id3v2_version != 3 &&
565	mp3->id3v2_version != 4) {
566	av_log(s, AV_LOG_ERROR, "Invalid ID3v2 version requested: %d. Only "
567	"3, 4 or 0 (disabled) are allowed.\n", mp3->id3v2_version);
568	return AVERROR(EINVAL);
569	}
570
571	/* check the streams -- we want exactly one audio and arbitrary number of
572	* video (attached pictures) */
573	mp3->audio_stream_idx = -1;
574	for (i = 0; i < s->nb_streams; i++) {
575	AVStream *st = s->streams[i];
576	if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
577	if (mp3->audio_stream_idx >= 0 \|\| st->codec->codec_id != AV_CODEC_ID_MP3) {
578	av_log(s, AV_LOG_ERROR, "Invalid audio stream. Exactly one MP3 "
579	"audio stream is required.\n");
580	return AVERROR(EINVAL);
581	}
582	mp3->audio_stream_idx = i;
583	} else if (st->codec->codec_type != AVMEDIA_TYPE_VIDEO) {
584	av_log(s, AV_LOG_ERROR, "Only audio streams and pictures are allowed in MP3.\n");
585	return AVERROR(EINVAL);
586	}
587	}
588	if (mp3->audio_stream_idx < 0) {
589	av_log(s, AV_LOG_ERROR, "No audio stream present.\n");
590	return AVERROR(EINVAL);
591	}
592	mp3->pics_to_write = s->nb_streams - 1;
593
594	if (mp3->pics_to_write && !mp3->id3v2_version) {
595	av_log(s, AV_LOG_ERROR, "Attached pictures were requested, but the "
596	"ID3v2 header is disabled.\n");
597	return AVERROR(EINVAL);
598	}
599
600	if (mp3->id3v2_version) {
601	ff_id3v2_start(&mp3->id3, s->pb, mp3->id3v2_version, ID3v2_DEFAULT_MAGIC);
602	ret = ff_id3v2_write_metadata(s, &mp3->id3);
603	if (ret < 0)
604	return ret;
605	}
606
607	if (!mp3->pics_to_write) {
608	if (mp3->id3v2_version)
609	ff_id3v2_finish(&mp3->id3, s->pb, s->metadata_header_padding);
610	mp3_write_xing(s);
611	}
612
613	return 0;
614	}
615
616	AVOutputFormat ff_mp3_muxer = {
617	.name = "mp3",
618	.long_name = NULL_IF_CONFIG_SMALL("MP3 (MPEG audio layer 3)"),
619	.mime_type = "audio/mpeg",
620	.extensions = "mp3",
621	.priv_data_size = sizeof(MP3Context),
622	.audio_codec = AV_CODEC_ID_MP3,
623	.video_codec = AV_CODEC_ID_PNG,
624	.write_header = mp3_write_header,
625	.write_packet = mp3_write_packet,
626	.write_trailer = mp3_write_trailer,
627	.query_codec = query_codec,
628	.flags = AVFMT_NOTIMESTAMPS,
629	.priv_class = &mp3_muxer_class,
630	};
631	#endif