PeerStreamer

/*

 * Smacker demuxer

 * Copyright (c) 2006 Konstantin Shishkov

 *

 * 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

 */

/*

 * Based on http://wiki.multimedia.cx/index.php?title=Smacker

 */

#include "libavutil/bswap.h"

#include "libavutil/intreadwrite.h"

#include "avformat.h"

#define SMACKER_PAL 0x01

#define SMACKER_FLAG_RING_FRAME 0x01

enum SAudFlags {

    SMK_AUD_PACKED  = 0x80000000,

    SMK_AUD_16BITS  = 0x20000000,

    SMK_AUD_STEREO  = 0x10000000,

    SMK_AUD_BINKAUD = 0x08000000,

    SMK_AUD_USEDCT  = 0x04000000

};

typedef struct SmackerContext {

    /* Smacker file header */

    uint32_t magic;

    uint32_t width, height;

    uint32_t frames;

    int      pts_inc;

    uint32_t flags;

    uint32_t audio[7];

    uint32_t treesize;

    uint32_t mmap_size, mclr_size, full_size, type_size;

    uint32_t rates[7];

    uint32_t pad;

    /* frame info */

    uint32_t *frm_size;

    uint8_t  *frm_flags;

    /* internal variables */

    int cur_frame;

    int is_ver4;

    int64_t cur_pts;

    /* current frame for demuxing */

    uint8_t pal[768];

    int indexes[7];

    int videoindex;

    uint8_t *bufs[7];

    int buf_sizes[7];

    int stream_id[7];

    int curstream;

    int64_t nextpos;

    int64_t aud_pts[7];

} SmackerContext;

typedef struct SmackerFrame {

    int64_t pts;

    int stream;

} SmackerFrame;

/* palette used in Smacker */

static const uint8_t smk_pal[64] = {

    0x00, 0x04, 0x08, 0x0C, 0x10, 0x14, 0x18, 0x1C,

    0x20, 0x24, 0x28, 0x2C, 0x30, 0x34, 0x38, 0x3C,

    0x41, 0x45, 0x49, 0x4D, 0x51, 0x55, 0x59, 0x5D,

    0x61, 0x65, 0x69, 0x6D, 0x71, 0x75, 0x79, 0x7D,

    0x82, 0x86, 0x8A, 0x8E, 0x92, 0x96, 0x9A, 0x9E,

    0xA2, 0xA6, 0xAA, 0xAE, 0xB2, 0xB6, 0xBA, 0xBE,

    0xC3, 0xC7, 0xCB, 0xCF, 0xD3, 0xD7, 0xDB, 0xDF,

    0xE3, 0xE7, 0xEB, 0xEF, 0xF3, 0xF7, 0xFB, 0xFF

};

static int smacker_probe(AVProbeData *p)

{

    if(p->buf[0] == 'S' && p->buf[1] == 'M' && p->buf[2] == 'K'

        && (p->buf[3] == '2' || p->buf[3] == '4'))

        return AVPROBE_SCORE_MAX;

    else

        return 0;

}

static int smacker_read_header(AVFormatContext *s, AVFormatParameters *ap)

{

    ByteIOContext *pb = s->pb;

    SmackerContext *smk = s->priv_data;

    AVStream *st, *ast[7];

    int i, ret;

    int tbase;

    /* read and check header */

    smk->magic = get_le32(pb);

    if (smk->magic != MKTAG('S', 'M', 'K', '2') && smk->magic != MKTAG('S', 'M', 'K', '4'))

        return -1;

    smk->width = get_le32(pb);

    smk->height = get_le32(pb);

    smk->frames = get_le32(pb);

    smk->pts_inc = (int32_t)get_le32(pb);

    smk->flags = get_le32(pb);

    if(smk->flags & SMACKER_FLAG_RING_FRAME)

        smk->frames++;

    for(i = 0; i < 7; i++)

        smk->audio[i] = get_le32(pb);

    smk->treesize = get_le32(pb);

    if(smk->treesize >= UINT_MAX/4){ // smk->treesize + 16 must not overflow (this check is probably redundant)

        av_log(s, AV_LOG_ERROR, "treesize too large\n");

        return -1;

    }

//FIXME remove extradata "rebuilding"

    smk->mmap_size = get_le32(pb);

    smk->mclr_size = get_le32(pb);

    smk->full_size = get_le32(pb);

    smk->type_size = get_le32(pb);

    for(i = 0; i < 7; i++)

        smk->rates[i] = get_le32(pb);

    smk->pad = get_le32(pb);

    /* setup data */

    if(smk->frames > 0xFFFFFF) {

        av_log(s, AV_LOG_ERROR, "Too many frames: %i\n", smk->frames);

        return -1;

    }

    smk->frm_size = av_malloc(smk->frames * 4);

    smk->frm_flags = av_malloc(smk->frames);

    smk->is_ver4 = (smk->magic != MKTAG('S', 'M', 'K', '2'));

    /* read frame info */

    for(i = 0; i < smk->frames; i++) {

        smk->frm_size[i] = get_le32(pb);

    }

    for(i = 0; i < smk->frames; i++) {

        smk->frm_flags[i] = get_byte(pb);

    }

    /* init video codec */

    st = av_new_stream(s, 0);

    if (!st)

        return -1;

    smk->videoindex = st->index;

    st->codec->width = smk->width;

    st->codec->height = smk->height;

    st->codec->pix_fmt = PIX_FMT_PAL8;

    st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

    st->codec->codec_id = CODEC_ID_SMACKVIDEO;

    st->codec->codec_tag = smk->magic;

    /* Smacker uses 100000 as internal timebase */

    if(smk->pts_inc < 0)

        smk->pts_inc = -smk->pts_inc;

    else

        smk->pts_inc *= 100;

    tbase = 100000;

    av_reduce(&tbase, &smk->pts_inc, tbase, smk->pts_inc, (1UL<<31)-1);

    av_set_pts_info(st, 33, smk->pts_inc, tbase);

    st->duration = smk->frames;

    /* handle possible audio streams */

    for(i = 0; i < 7; i++) {

        smk->indexes[i] = -1;

        if(smk->rates[i] & 0xFFFFFF){

            ast[i] = av_new_stream(s, 0);

            smk->indexes[i] = ast[i]->index;

            ast[i]->codec->codec_type = AVMEDIA_TYPE_AUDIO;

            if (smk->rates[i] & SMK_AUD_BINKAUD) {

                ast[i]->codec->codec_id = CODEC_ID_BINKAUDIO_RDFT;

            } else if (smk->rates[i] & SMK_AUD_USEDCT) {

                ast[i]->codec->codec_id = CODEC_ID_BINKAUDIO_DCT;

            } else if (smk->rates[i] & SMK_AUD_PACKED){

                ast[i]->codec->codec_id = CODEC_ID_SMACKAUDIO;

                ast[i]->codec->codec_tag = MKTAG('S', 'M', 'K', 'A');

            } else {

                ast[i]->codec->codec_id = CODEC_ID_PCM_U8;

            }

            ast[i]->codec->channels = (smk->rates[i] & SMK_AUD_STEREO) ? 2 : 1;

            ast[i]->codec->sample_rate = smk->rates[i] & 0xFFFFFF;

            ast[i]->codec->bits_per_coded_sample = (smk->rates[i] & SMK_AUD_16BITS) ? 16 : 8;

            if(ast[i]->codec->bits_per_coded_sample == 16 && ast[i]->codec->codec_id == CODEC_ID_PCM_U8)

                ast[i]->codec->codec_id = CODEC_ID_PCM_S16LE;

            av_set_pts_info(ast[i], 64, 1, ast[i]->codec->sample_rate

                    * ast[i]->codec->channels * ast[i]->codec->bits_per_coded_sample / 8);

        }

    }

    /* load trees to extradata, they will be unpacked by decoder */

    st->codec->extradata = av_malloc(smk->treesize + 16);

    st->codec->extradata_size = smk->treesize + 16;

    if(!st->codec->extradata){

        av_log(s, AV_LOG_ERROR, "Cannot allocate %i bytes of extradata\n", smk->treesize + 16);

        av_free(smk->frm_size);

        av_free(smk->frm_flags);

        return -1;

    }

    ret = get_buffer(pb, st->codec->extradata + 16, st->codec->extradata_size - 16);

    if(ret != st->codec->extradata_size - 16){

        av_free(smk->frm_size);

        av_free(smk->frm_flags);

        return AVERROR(EIO);

    }

    ((int32_t*)st->codec->extradata)[0] = le2me_32(smk->mmap_size);

    ((int32_t*)st->codec->extradata)[1] = le2me_32(smk->mclr_size);

    ((int32_t*)st->codec->extradata)[2] = le2me_32(smk->full_size);

    ((int32_t*)st->codec->extradata)[3] = le2me_32(smk->type_size);

    smk->curstream = -1;

    smk->nextpos = url_ftell(pb);

    return 0;

}

static int smacker_read_packet(AVFormatContext *s, AVPacket *pkt)

{

    SmackerContext *smk = s->priv_data;

    int flags;

    int ret;

    int i;

    int frame_size = 0;

    int palchange = 0;

    int pos;

    if (url_feof(s->pb) || smk->cur_frame >= smk->frames)

        return AVERROR(EIO);

    /* if we demuxed all streams, pass another frame */

    if(smk->curstream < 0) {

        url_fseek(s->pb, smk->nextpos, 0);

        frame_size = smk->frm_size[smk->cur_frame] & (~3);

        flags = smk->frm_flags[smk->cur_frame];

        /* handle palette change event */

        pos = url_ftell(s->pb);

        if(flags & SMACKER_PAL){

            int size, sz, t, off, j, pos;

            uint8_t *pal = smk->pal;

            uint8_t oldpal[768];

            memcpy(oldpal, pal, 768);

            size = get_byte(s->pb);

            size = size * 4 - 1;

            frame_size -= size;

            frame_size--;

            sz = 0;

            pos = url_ftell(s->pb) + size;

            while(sz < 256){

                t = get_byte(s->pb);

                if(t & 0x80){ /* skip palette entries */

                    sz += (t & 0x7F) + 1;

                    pal += ((t & 0x7F) + 1) * 3;

                } else if(t & 0x40){ /* copy with offset */

                    off = get_byte(s->pb) * 3;

                    j = (t & 0x3F) + 1;

                    while(j-- && sz < 256) {

                        *pal++ = oldpal[off + 0];

                        *pal++ = oldpal[off + 1];

                        *pal++ = oldpal[off + 2];

                        sz++;

                        off += 3;

                    }

                } else { /* new entries */

                    *pal++ = smk_pal[t];

                    *pal++ = smk_pal[get_byte(s->pb) & 0x3F];

                    *pal++ = smk_pal[get_byte(s->pb) & 0x3F];

                    sz++;

                }

            }

            url_fseek(s->pb, pos, 0);

            palchange |= 1;

        }

        flags >>= 1;

        smk->curstream = -1;

        /* if audio chunks are present, put them to stack and retrieve later */

        for(i = 0; i < 7; i++) {

            if(flags & 1) {

                int size;

                size = get_le32(s->pb) - 4;

                frame_size -= size;

                frame_size -= 4;

                smk->curstream++;

                smk->bufs[smk->curstream] = av_realloc(smk->bufs[smk->curstream], size);

                smk->buf_sizes[smk->curstream] = size;

                ret = get_buffer(s->pb, smk->bufs[smk->curstream], size);

                if(ret != size)

                    return AVERROR(EIO);

                smk->stream_id[smk->curstream] = smk->indexes[i];

            }

            flags >>= 1;

        }

        if (av_new_packet(pkt, frame_size + 768))

            return AVERROR(ENOMEM);

        if(smk->frm_size[smk->cur_frame] & 1)

            palchange |= 2;

        pkt->data[0] = palchange;

        memcpy(pkt->data + 1, smk->pal, 768);

        ret = get_buffer(s->pb, pkt->data + 769, frame_size);

        if(ret != frame_size)

            return AVERROR(EIO);

        pkt->stream_index = smk->videoindex;

        pkt->size = ret + 769;

        smk->cur_frame++;

        smk->nextpos = url_ftell(s->pb);

    } else {

        if (av_new_packet(pkt, smk->buf_sizes[smk->curstream]))

            return AVERROR(ENOMEM);

        memcpy(pkt->data, smk->bufs[smk->curstream], smk->buf_sizes[smk->curstream]);

        pkt->size = smk->buf_sizes[smk->curstream];

        pkt->stream_index = smk->stream_id[smk->curstream];

        pkt->pts = smk->aud_pts[smk->curstream];

        smk->aud_pts[smk->curstream] += AV_RL32(pkt->data);

        smk->curstream--;

    }

    return 0;

}

static int smacker_read_close(AVFormatContext *s)

{

    SmackerContext *smk = s->priv_data;

    int i;

    for(i = 0; i < 7; i++)

        if(smk->bufs[i])

            av_free(smk->bufs[i]);

    if(smk->frm_size)

        av_free(smk->frm_size);

    if(smk->frm_flags)

        av_free(smk->frm_flags);

    return 0;

}

AVInputFormat smacker_demuxer = {

    "smk",

    NULL_IF_CONFIG_SMALL("Smacker video"),

    sizeof(SmackerContext),

    smacker_probe,

    smacker_read_header,

    smacker_read_packet,

    smacker_read_close,

};