asf-enc.c

ffmpeg源码分析

/*
 * Adaptive stream format encoder
 * Copyright (c) 2000, 2001 Fabrice Bellard.
 *
 * This library 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 of the License, or (at your option) any later version.
 *
 * This library 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 this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */
#include "avformat.h"
#include "avi.h"
#include "asf.h"

#undef NDEBUG
#include <assert.h>

#ifdef CONFIG_MUXERS


#define ASF_INDEXED_INTERVAL    10000000
#define ASF_INDEX_BLOCK         600

#define ASF_PACKET_ERROR_CORRECTION_DATA_SIZE 0x2
#define ASF_PACKET_ERROR_CORRECTION_FLAGS (\
                ASF_PACKET_FLAG_ERROR_CORRECTION_PRESENT | \
                ASF_PACKET_ERROR_CORRECTION_DATA_SIZE\
                )

#if (ASF_PACKET_ERROR_CORRECTION_FLAGS != 0)
#   define ASF_PACKET_ERROR_CORRECTION_FLAGS_FIELD_SIZE 1
#else
#   define ASF_PACKET_ERROR_CORRECTION_FLAGS_FIELD_SIZE 0
#endif

#define ASF_PPI_PROPERTY_FLAGS (\
                ASF_PL_FLAG_REPLICATED_DATA_LENGTH_FIELD_IS_BYTE | \
                ASF_PL_FLAG_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_IS_DWORD | \
                ASF_PL_FLAG_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_IS_BYTE | \
                ASF_PL_FLAG_STREAM_NUMBER_LENGTH_FIELD_IS_BYTE \
                )

#define ASF_PPI_LENGTH_TYPE_FLAGS 0

#define ASF_PAYLOAD_FLAGS ASF_PL_FLAG_PAYLOAD_LENGTH_FIELD_IS_WORD

#if (ASF_PPI_FLAG_SEQUENCE_FIELD_IS_BYTE == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_SEQUENCE_FIELD_SIZE))
#   define ASF_PPI_SEQUENCE_FIELD_SIZE 1
#endif
#if (ASF_PPI_FLAG_SEQUENCE_FIELD_IS_WORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_SEQUENCE_FIELD_SIZE))
#   define ASF_PPI_SEQUENCE_FIELD_SIZE 2
#endif
#if (ASF_PPI_FLAG_SEQUENCE_FIELD_IS_DWORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_SEQUENCE_FIELD_SIZE))
#   define ASF_PPI_SEQUENCE_FIELD_SIZE 4
#endif
#ifndef ASF_PPI_SEQUENCE_FIELD_SIZE
#   define ASF_PPI_SEQUENCE_FIELD_SIZE 0
#endif


#if (ASF_PPI_FLAG_PACKET_LENGTH_FIELD_IS_BYTE == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PACKET_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PACKET_LENGTH_FIELD_SIZE 1
#endif
#if (ASF_PPI_FLAG_PACKET_LENGTH_FIELD_IS_WORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PACKET_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PACKET_LENGTH_FIELD_SIZE 2
#endif
#if (ASF_PPI_FLAG_PACKET_LENGTH_FIELD_IS_DWORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PACKET_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PACKET_LENGTH_FIELD_SIZE 4
#endif
#ifndef ASF_PPI_PACKET_LENGTH_FIELD_SIZE
#   define ASF_PPI_PACKET_LENGTH_FIELD_SIZE 0
#endif

#if (ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_BYTE == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PADDING_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PADDING_LENGTH_FIELD_SIZE 1
#endif
#if (ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_WORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PADDING_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PADDING_LENGTH_FIELD_SIZE 2
#endif
#if (ASF_PPI_FLAG_PADDING_LENGTH_FIELD_IS_DWORD == (ASF_PPI_LENGTH_TYPE_FLAGS & ASF_PPI_MASK_PADDING_LENGTH_FIELD_SIZE))
#   define ASF_PPI_PADDING_LENGTH_FIELD_SIZE 4
#endif
#ifndef ASF_PPI_PADDING_LENGTH_FIELD_SIZE
#   define ASF_PPI_PADDING_LENGTH_FIELD_SIZE 0
#endif

#if (ASF_PL_FLAG_REPLICATED_DATA_LENGTH_FIELD_IS_BYTE == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_REPLICATED_DATA_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE 1
#endif
#if (ASF_PL_FLAG_REPLICATED_DATA_LENGTH_FIELD_IS_WORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_REPLICATED_DATA_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE 2
#endif
#if (ASF_PL_FLAG_REPLICATED_DATA_LENGTH_FIELD_IS_DWORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_REPLICATED_DATA_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE 4
#endif
#ifndef ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE
#   define ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE 0
#endif

#if (ASF_PL_FLAG_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_IS_BYTE == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE 1
#endif
#if (ASF_PL_FLAG_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_IS_WORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE 2
#endif
#if (ASF_PL_FLAG_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_IS_DWORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_OFFSET_INTO_MEDIA_OBJECT_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE 4
#endif
#ifndef ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE
#   define ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE 0
#endif

#if (ASF_PL_FLAG_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_IS_BYTE == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE 1
#endif
#if (ASF_PL_FLAG_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_IS_WORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE 2
#endif
#if (ASF_PL_FLAG_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_IS_DWORD == (ASF_PPI_PROPERTY_FLAGS & ASF_PL_MASK_MEDIA_OBJECT_NUMBER_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE 4
#endif
#ifndef ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE
#   define ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE 0
#endif

#if (ASF_PL_FLAG_PAYLOAD_LENGTH_FIELD_IS_BYTE == (ASF_PAYLOAD_FLAGS & ASF_PL_MASK_PAYLOAD_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_LENGTH_FIELD_SIZE 1
#endif
#if (ASF_PL_FLAG_PAYLOAD_LENGTH_FIELD_IS_WORD == (ASF_PAYLOAD_FLAGS & ASF_PL_MASK_PAYLOAD_LENGTH_FIELD_SIZE))
#   define ASF_PAYLOAD_LENGTH_FIELD_SIZE 2
#endif
#ifndef ASF_PAYLOAD_LENGTH_FIELD_SIZE
#   define ASF_PAYLOAD_LENGTH_FIELD_SIZE 0
#endif

#define PACKET_HEADER_MIN_SIZE (\
                ASF_PACKET_ERROR_CORRECTION_FLAGS_FIELD_SIZE + \
                ASF_PACKET_ERROR_CORRECTION_DATA_SIZE + \
                1 + /*Length Type Flags*/ \
                1 + /*Property Flags*/ \
                ASF_PPI_PACKET_LENGTH_FIELD_SIZE + \
                ASF_PPI_SEQUENCE_FIELD_SIZE + \
                ASF_PPI_PADDING_LENGTH_FIELD_SIZE + \
                4 + /*Send Time Field*/ \
                2   /*Duration Field*/ \
                )


// Replicated Data shall be at least 8 bytes long.
#define ASF_PAYLOAD_REPLICATED_DATA_LENGTH 0x08

#define PAYLOAD_HEADER_SIZE_SINGLE_PAYLOAD (\
                1 + /*Stream Number*/ \
                ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE + \
                ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE + \
                ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE + \
                ASF_PAYLOAD_REPLICATED_DATA_LENGTH \
                )

#define PAYLOAD_HEADER_SIZE_MULTIPLE_PAYLOADS (\
                1 + /*Stream Number*/ \
                ASF_PAYLOAD_MEDIA_OBJECT_NUMBER_FIELD_SIZE + \
                ASF_PAYLOAD_OFFSET_INTO_MEDIA_OBJECT_FIELD_SIZE + \
                ASF_PAYLOAD_REPLICATED_DATA_LENGTH_FIELD_SIZE + \
                ASF_PAYLOAD_REPLICATED_DATA_LENGTH + \
                ASF_PAYLOAD_LENGTH_FIELD_SIZE \
                )

#define SINGLE_PAYLOAD_DATA_LENGTH (\
                PACKET_SIZE - \
                PACKET_HEADER_MIN_SIZE - \
                PAYLOAD_HEADER_SIZE_SINGLE_PAYLOAD \
                )

#define MULTI_PAYLOAD_CONSTANT (\
                PACKET_SIZE - \
                PACKET_HEADER_MIN_SIZE - \
                1 - /*Payload Flags*/ \
                2*PAYLOAD_HEADER_SIZE_MULTIPLE_PAYLOADS \
                )

static int preroll_time = 2000;

static const uint8_t error_spread_ADPCM_G726[] = { 0x01, 0x90, 0x01, 0x90, 0x01, 0x01, 0x00, 0x00 };

static void put_guid(ByteIOContext *s, const GUID *g)
{
    int i;

    put_le32(s, g->v1);
    put_le16(s, g->v2);
    put_le16(s, g->v3);
    for(i=0;i<8;i++)
        put_byte(s, g->v4[i]);
}

static void put_str16(ByteIOContext *s, const char *tag)
{
    int c;

    put_le16(s,strlen(tag) + 1);
    for(;;) {
        c = (uint8_t)*tag++;
        put_le16(s, c);
        if (c == '\0')
            break;
    }
}

static void put_str16_nolen(ByteIOContext *s, const char *tag)
{
    int c;

    for(;;) {
        c = (uint8_t)*tag++;
        put_le16(s, c);
        if (c == '\0')
            break;
    }
}

static int64_t put_header(ByteIOContext *pb, const GUID *g)
{
    int64_t pos;

    pos = url_ftell(pb);
    put_guid(pb, g);
    put_le64(pb, 24);
    return pos;
}

/* update header size */
static void end_header(ByteIOContext *pb, int64_t pos)
{
    int64_t pos1;

    pos1 = url_ftell(pb);
    url_fseek(pb, pos + 16, SEEK_SET);
    put_le64(pb, pos1 - pos);
    url_fseek(pb, pos1, SEEK_SET);
}

/* write an asf chunk (only used in streaming case) */
static void put_chunk(AVFormatContext *s, int type, int payload_length, int flags)
{
    ASFContext *asf = s->priv_data;
    ByteIOContext *pb = &s->pb;
    int length;

    length = payload_length + 8;
    put_le16(pb, type);
    put_le16(pb, length);    //size
    put_le32(pb, asf->seqno);//sequence number
    put_le16(pb, flags); /* unknown bytes */
    put_le16(pb, length);    //size_confirm
    asf->seqno++;
}

/* convert from unix to windows time */
static int64_t unix_to_file_time(int ti)
{
    int64_t t;

    t = ti * int64_t_C(10000000);
    t += int64_t_C(116444736000000000);
    return t;
}

/* write the header (used two times if non streamed) */
static int asf_write_header1(AVFormatContext *s, int64_t file_size, int64_t data_chunk_size)
{
    ASFContext *asf = s->priv_data;
    ByteIOContext *pb = &s->pb;
    int header_size, n, extra_size, extra_size2, wav_extra_size, file_time;
    int has_title;
    AVCodecContext *enc;
    int64_t header_offset, cur_pos, hpos;
    int bit_rate;

    has_title = (s->title[0] || s->author[0] || s->copyright[0] || s->comment[0]);

    bit_rate = 0;
    for(n=0;n<s->nb_streams;n++) {
        enc = s->streams[n]->codec;

        av_set_pts_info(s->streams[n], 32, 1, 1000); /* 32 bit pts in ms */

        bit_rate += enc->bit_rate;
    }

    if (asf->is_streamed) {
        put_chunk(s, 0x4824, 0, 0xc00); /* start of stream (length will be patched later) */
    }

    put_guid(pb, &asf_header);
    put_le64(pb, -1); /* header length, will be patched after */
    put_le32(pb, 3 + has_title + s->nb_streams); /* number of chunks in header */
    put_byte(pb, 1); /* ??? */
    put_byte(pb, 2); /* ??? */

    /* file header */
    header_offset = url_ftell(pb);
    hpos = put_header(pb, &file_header);
    put_guid(pb, &my_guid);
    put_le64(pb, file_size);
    file_time = 0;
    put_le64(pb, unix_to_file_time(file_time));
    put_le64(pb, asf->nb_packets); /* number of packets */
    put_le64(pb, asf->duration); /* end time stamp (in 100ns units) */
    put_le64(pb, asf->duration); /* duration (in 100ns units) */
    put_le32(pb, preroll_time); /* start time stamp */
    put_le32(pb, 0); /* ??? */
    put_le32(pb, asf->is_streamed ? 1 : 0); /* ??? */
    put_le32(pb, asf->packet_size); /* packet size */
    put_le32(pb, asf->packet_size); /* packet size */
    put_le32(pb, bit_rate); /* Nominal data rate in bps */
    end_header(pb, hpos);

    /* unknown headers */
    hpos = put_header(pb, &head1_guid);
    put_guid(pb, &head2_guid);
    put_le32(pb, 6);
    put_le16(pb, 0);
    end_header(pb, hpos);

    /* title and other infos */
    if (has_title) {
        hpos = put_header(pb, &comment_header);
        if ( s->title[0]     ) { put_le16(pb, 2 * (strlen(s->title    ) + 1)); } else { put_le16(pb, 0); }
        if ( s->author[0]    ) { put_le16(pb, 2 * (strlen(s->author   ) + 1)); } else { put_le16(pb, 0); }
        if ( s->copyright[0] ) { put_le16(pb, 2 * (strlen(s->copyright) + 1)); } else { put_le16(pb, 0); }
        if ( s->comment[0]   ) { put_le16(pb, 2 * (strlen(s->comment  ) + 1)); } else { put_le16(pb, 0); }
        put_le16(pb, 0);
        if ( s->title[0]     ) put_str16_nolen(pb, s->title);
        if ( s->author[0]    ) put_str16_nolen(pb, s->author);
        if ( s->copyright[0] ) put_str16_nolen(pb, s->copyright);
        if ( s->comment[0]   ) put_str16_nolen(pb, s->comment);
        end_header(pb, hpos);
    }

    /* stream headers */
    for(n=0;n<s->nb_streams;n++) {
        int64_t es_pos;
        uint8_t *er_spr = NULL;
        int er_spr_len = 0;
        //        ASFStream *stream = &asf->streams[n];

        enc = s->streams[n]->codec;
        asf->streams[n].num = n + 1;
        asf->streams[n].seq = 0;


        if (enc->codec_type == CODEC_TYPE_AUDIO) {
            if (enc->codec_id == CODEC_ID_ADPCM_G726) {
                er_spr     = (uint8_t *)error_spread_ADPCM_G726;
                er_spr_len = sizeof(error_spread_ADPCM_G726);
            }
        }

        switch(enc->codec_type) {
        case CODEC_TYPE_AUDIO:
            wav_extra_size = 0;
            extra_size = 18 + wav_extra_size;
            extra_size2 = er_spr_len;
            break;
        default:
        case CODEC_TYPE_VIDEO:
            wav_extra_size = enc->extradata_size;
            extra_size = 0x33 + wav_extra_size;
            extra_size2 = 0;
            break;
        }

        hpos = put_header(pb, &stream_header);
        if (enc->codec_type == CODEC_TYPE_AUDIO) {
            put_guid(pb, &audio_stream);
            if ((er_spr != NULL) && (er_spr_len != 0)) {
                put_guid(pb, &audio_conceal_spread);
            } else {
                put_guid(pb, &video_conceal_none);
            }
        } else {
            put_guid(pb, &video_stream);
            put_guid(pb, &video_conceal_none);
        }
        put_le64(pb, 0); /* ??? */
        es_pos = url_ftell(pb);
        put_le32(pb, extra_size); /* wav header len */
        put_le32(pb, extra_size2); /* additional data len */
        put_le16(pb, n + 1); /* stream number */
        put_le32(pb, 0); /* ??? */

        if (enc->codec_type == CODEC_TYPE_AUDIO) {
            /* WAVEFORMATEX header */
            int wavsize = put_wav_header(pb, enc);
            if ((enc->codec_id != CODEC_ID_MP3) && (enc->codec_id != CODEC_ID_MP2) && (enc->codec_id != CODEC_ID_ADPCM_IMA_WAV) && (enc->extradata_size==0)) {
                wavsize += 2;
                put_le16(pb, 0);
            }

            if (wavsize < 0)
                return -1;
            if (wavsize != extra_size) {
                cur_pos = url_ftell(pb);
                url_fseek(pb, es_pos, SEEK_SET);
                put_le32(pb, wavsize); /* wav header len */
                url_fseek(pb, cur_pos, SEEK_SET);
            }
            /* ERROR Correction */
            if ((er_spr != NULL) && (er_spr_len != 0))
                put_buffer(pb, er_spr, er_spr_len);
        } else {
            put_le32(pb, enc->width);
            put_le32(pb, enc->height);
            put_byte(pb, 2); /* ??? */
            put_le16(pb, 40 + enc->extradata_size); /* size */

            /* BITMAPINFOHEADER header */
            put_bmp_header(pb, enc, codec_bmp_tags, 1);
        }
        end_header(pb, hpos);
    }