Initial revision

Originally committed as revision 5 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 599 insertions, 0 deletions

diff --git a/libav/ffm.c b/libav/ffm.c
new file mode 100644
index 0000000000..76e7613286
--- /dev/null
+++ b/libav/ffm.c
@@ -0,0 +1,599 @@
+/*
+ * FFM (ffserver live feed) encoder and decoder
+ * Copyright (c) 2001 Gerard Lantau.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "avformat.h"
+
+/* The FFM file is made of blocks of fixed size */
+#define FFM_HEADER_SIZE 14
+#define PACKET_ID       0x666d
+
+/* each packet contains frames (which can span several packets */
+#define FRAME_HEADER_SIZE    5
+#define FLAG_KEY_FRAME       0x01
+
+typedef struct FFMStream {
+    INT64 pts;
+} FFMStream;
+
+enum {
+    READ_HEADER,
+    READ_DATA,
+};
+
+typedef struct FFMContext {
+    /* only reading mode */
+    offset_t write_index, file_size;
+    int read_state; 
+    UINT8 header[FRAME_HEADER_SIZE];
+
+    /* read and write */
+    int first_packet; /* true if first packet, needed to set the discontinuity tag */
+    int packet_size;
+    int frame_offset;
+    INT64 pts;
+    UINT8 *packet_ptr, *packet_end;
+    UINT8 packet[1]; /* must be last */
+} FFMContext;
+
+static void flush_packet(AVFormatContext *s)
+{
+    FFMContext *ffm = s->priv_data;
+    int fill_size, h;
+    ByteIOContext *pb = &s->pb;
+
+    fill_size = ffm->packet_end - ffm->packet_ptr;
+    memset(ffm->packet_ptr, 0, fill_size);
+    
+    /* put header */
+    put_be16(pb, PACKET_ID); 
+    put_be16(pb, fill_size);
+    put_be64(pb, ffm->pts);
+    h = ffm->frame_offset;
+    if (ffm->first_packet)
+        h |= 0x8000;
+    put_be16(pb, h);
+    put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
+
+    /* prepare next packet */
+    ffm->frame_offset = 0; /* no key frame */
+    ffm->pts = 0; /* no pts */
+    ffm->packet_ptr = ffm->packet;
+    ffm->first_packet = 0;
+}
+
+/* 'first' is true if first data of a frame */
+static void ffm_write_data(AVFormatContext *s, 
+                           UINT8 *buf, int size, 
+                           INT64 pts, int first)
+{
+    FFMContext *ffm = s->priv_data;
+    int len;
+
+    if (first && ffm->frame_offset == 0)
+        ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
+    if (first && ffm->pts == 0)
+        ffm->pts = pts;
+
+    /* write as many packets as needed */
+    while (size > 0) {
+        len = ffm->packet_end - ffm->packet_ptr;
+        if (len > size)
+            len = size;
+        memcpy(ffm->packet_ptr, buf, len);
+        
+        ffm->packet_ptr += len;
+        buf += len;
+        size -= len;
+        if (ffm->packet_ptr >= ffm->packet_end) {
+            /* special case : no pts in packet : we leave the current one */
+            if (ffm->pts == 0)
+                ffm->pts = pts;
+
+            flush_packet(s);
+        }
+    }
+}
+
+static int ffm_write_header(AVFormatContext *s)
+{
+    AVStream *st;
+    FFMStream *fst;
+    FFMContext *ffm;
+    ByteIOContext *pb = &s->pb;
+    AVCodecContext *codec;
+    int bit_rate, i;
+
+    ffm = av_mallocz(sizeof(FFMContext) + FFM_PACKET_SIZE);
+    if (!ffm)
+        return -1;
+
+    s->priv_data = ffm;
+    ffm->packet_size = FFM_PACKET_SIZE;
+    
+    /* header */
+    put_tag(pb, "FFM1");
+    put_be32(pb, ffm->packet_size);
+    /* XXX: store write position in other file ? */
+    put_be64(pb, ffm->packet_size); /* current write position */
+
+    put_be32(pb, s->nb_streams);
+    bit_rate = 0;
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        bit_rate += st->codec.bit_rate;
+    }
+    put_be32(pb, bit_rate);
+
+    /* list of streams */
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        fst = av_mallocz(sizeof(FFMStream) + ffm->packet_size);
+        if (!fst)
+            goto fail;
+        st->priv_data = fst;
+
+        codec = &st->codec;
+        /* generic info */
+        put_be32(pb, codec->codec_id);
+        put_byte(pb, codec->codec_type);
+        put_be32(pb, codec->bit_rate);
+        /* specific info */
+        switch(codec->codec_type) {
+        case CODEC_TYPE_VIDEO:
+            put_be32(pb, (codec->frame_rate * 1000) / FRAME_RATE_BASE);
+            put_be16(pb, codec->width);
+            put_be16(pb, codec->height);
+            break;
+        case CODEC_TYPE_AUDIO:
+            put_be32(pb, codec->sample_rate);
+            put_le16(pb, codec->channels);
+            break;
+        }
+        /* hack to have real time */
+        fst->pts = gettime();
+    }
+
+    /* flush until end of block reached */
+    while ((url_ftell(pb) % ffm->packet_size) != 0)
+        put_byte(pb, 0);
+
+    put_flush_packet(pb);
+
+    /* init packet mux */
+    ffm->packet_ptr = ffm->packet;
+    ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
+    ffm->frame_offset = 0;
+    ffm->pts = 0;
+    ffm->first_packet = 1;
+
+    return 0;
+ fail:
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        fst = st->priv_data;
+        if (fst)
+            free(fst);
+    }
+    free(ffm);
+    return -1;
+}
+
+static int ffm_write_packet(AVFormatContext *s, int stream_index,
+                            UINT8 *buf, int size)
+{
+    AVStream *st = s->streams[stream_index];
+    FFMStream *fst = st->priv_data;
+    INT64 pts;
+    UINT8 header[FRAME_HEADER_SIZE];
+
+    pts = fst->pts;
+    /* packet size & key_frame */
+    header[0] = stream_index;
+    header[1] = 0;
+    if (st->codec.key_frame)
+        header[1] |= FLAG_KEY_FRAME;
+    header[2] = (size >> 16) & 0xff;
+    header[3] = (size >> 8) & 0xff;
+    header[4] = size & 0xff;
+    ffm_write_data(s, header, FRAME_HEADER_SIZE, pts, 1);
+    ffm_write_data(s, buf, size, pts, 0);
+
+    if (st->codec.codec_type == CODEC_TYPE_AUDIO) {
+        fst->pts += (INT64)((float)st->codec.frame_size / st->codec.sample_rate * 1000000.0);
+    } else {
+        fst->pts += (INT64)(1000000.0 * FRAME_RATE_BASE / (float)st->codec.frame_rate);
+    }
+    return 0;
+}
+
+static int ffm_write_trailer(AVFormatContext *s)
+{
+    ByteIOContext *pb = &s->pb;
+    FFMContext *ffm = s->priv_data;
+    int i;
+
+    /* flush packets */
+    if (ffm->packet_ptr > ffm->packet)
+        flush_packet(s);
+
+    put_flush_packet(pb);
+
+    for(i=0;i<s->nb_streams;i++)
+        free(s->streams[i]->priv_data);
+    free(ffm);
+    return 0;
+}
+
+/* ffm demux */
+
+static int ffm_is_avail_data(AVFormatContext *s, int size)
+{
+    FFMContext *ffm = s->priv_data;
+    offset_t pos, avail_size;
+    int len;
+
+    len = ffm->packet_end - ffm->packet_ptr;
+    if (size <= len)
+        return 1;
+    pos = url_ftell(&s->pb);
+    if (pos == ffm->write_index) {
+        /* exactly at the end of stream */
+        return 0;
+    } else if (pos < ffm->write_index) {
+        avail_size = ffm->write_index - pos;
+    } else {
+        avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
+    }
+    avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
+    if (size <= avail_size)
+        return 1;
+    else
+        return 0;
+}
+
+/* first is true if we read the frame header */
+static int ffm_read_data(AVFormatContext *s, 
+                          UINT8 *buf, int size, int first)
+{
+    FFMContext *ffm = s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    int len, fill_size, size1, frame_offset;
+
+    size1 = size;
+    while (size > 0) {
+    redo:
+        len = ffm->packet_end - ffm->packet_ptr;
+        if (len > size)
+            len = size;
+        if (len == 0) {
+            if (url_ftell(pb) == ffm->file_size)
+                url_fseek(pb, ffm->packet_size, SEEK_SET);
+            get_be16(pb); /* PACKET_ID */
+            fill_size = get_be16(pb);
+            ffm->pts = get_be64(pb);
+            frame_offset = get_be16(pb);
+            get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
+            ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
+            /* if first packet or resynchronization packet, we must
+               handle it specifically */
+            if (ffm->first_packet || (frame_offset & 0x8000)) {
+                ffm->first_packet = 0;
+                ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
+                if (!first)
+                    break;
+            } else {
+                ffm->packet_ptr = ffm->packet;
+            }
+            goto redo;
+        }
+        memcpy(buf, ffm->packet_ptr, len);
+        buf += len;
+        ffm->packet_ptr += len;
+        size -= len;
+        first = 0;
+    }
+    return size1 - size;
+}
+
+
+static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    AVStream *st;
+    FFMStream *fst;
+    FFMContext *ffm;
+    ByteIOContext *pb = &s->pb;
+    AVCodecContext *codec;
+    int i;
+    UINT32 tag;
+
+    ffm = av_mallocz(sizeof(FFMContext) + FFM_PACKET_SIZE);
+    if (!ffm)
+        return -1;
+
+    s->priv_data = ffm;
+
+    /* header */
+    tag = get_le32(pb);
+    if (tag != MKTAG('F', 'F', 'M', '1'))
+        goto fail;
+    ffm->packet_size = get_be32(pb);
+    if (ffm->packet_size != FFM_PACKET_SIZE)
+        goto fail;
+    ffm->write_index = get_be64(pb);
+    /* get also filesize */
+    if (!url_is_streamed(pb)) {
+        ffm->file_size = url_filesize(url_fileno(pb));
+    } else {
+        ffm->file_size = (1ULL << 63) - 1;
+    }
+
+    s->nb_streams = get_be32(pb);
+    get_be32(pb); /* total bitrate */
+    /* read each stream */
+    for(i=0;i<s->nb_streams;i++) {
+        st = av_mallocz(sizeof(AVStream));
+        if (!st)
+            goto fail;
+        s->streams[i] = st;
+        fst = av_mallocz(sizeof(FFMStream) + ffm->packet_size);
+        if (!fst)
+            goto fail;
+        st->priv_data = fst;
+
+        codec = &st->codec;
+        /* generic info */
+        st->codec.codec_id = get_be32(pb);
+        st->codec.codec_type = get_byte(pb); /* codec_type */
+        codec->bit_rate = get_be32(pb);
+        /* specific info */
+        switch(codec->codec_type) {
+        case CODEC_TYPE_VIDEO:
+            codec->frame_rate = ((INT64)get_be32(pb) * FRAME_RATE_BASE) / 1000;
+            codec->width = get_be16(pb);
+            codec->height = get_be16(pb);
+            break;
+        case CODEC_TYPE_AUDIO:
+            codec->sample_rate = get_be32(pb);
+            codec->channels = get_le16(pb);
+            break;
+        }
+
+    }
+
+    /* get until end of block reached */
+    while ((url_ftell(pb) % ffm->packet_size) != 0)
+        get_byte(pb);
+
+    /* init packet demux */
+    ffm->packet_ptr = ffm->packet;
+    ffm->packet_end = ffm->packet;
+    ffm->frame_offset = 0;
+    ffm->pts = 0;
+    ffm->read_state = READ_HEADER;
+    ffm->first_packet = 1;
+    return 0;
+ fail:
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        if (st) {
+            fst = st->priv_data;
+            if (fst)
+                free(fst);
+            free(st);
+        }
+    }
+    if (ffm)
+        free(ffm);
+    return -1;
+}
+
+/* return < 0 if eof */
+static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    int size;
+    FFMContext *ffm = s->priv_data;
+
+    switch(ffm->read_state) {
+    case READ_HEADER:
+        if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE))
+            return -EAGAIN;
+#if 0
+        printf("pos=%08Lx spos=%Lx, write_index=%Lx size=%Lx\n", 
+               url_ftell(&s->pb), s->pb.pos, ffm->write_index, ffm->file_size);
+#endif
+        if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) != FRAME_HEADER_SIZE)
+            return -EAGAIN;
+            
+#if 0
+        {
+            int i;
+            for(i=0;i<FRAME_HEADER_SIZE;i++)
+                printf("%02x ", ffm->header[i]);
+            printf("\n");
+        }
+#endif
+        ffm->read_state = READ_DATA;
+        /* fall thru */
+    case READ_DATA:
+        size = (ffm->header[2] << 16) | (ffm->header[3] << 8) | ffm->header[4];
+        if (!ffm_is_avail_data(s, size)) {
+            return -EAGAIN;
+        }
+
+        av_new_packet(pkt, size);
+        pkt->stream_index = ffm->header[0];
+        if (ffm->header[1] & FLAG_KEY_FRAME)
+            pkt->flags |= PKT_FLAG_KEY;
+    
+        ffm->read_state = READ_HEADER;
+        if (ffm_read_data(s, pkt->data, size, 0) != size) {
+            /* bad case: desynchronized packet. we cancel all the packet loading */
+            av_free_packet(pkt);
+            return -EAGAIN;
+        }
+        break;
+    }
+    return 0;
+}
+
+//#define DEBUG_SEEK
+
+/* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
+   by the write position inside this function */
+static void ffm_seek1(AVFormatContext *s, offset_t pos1)
+{
+    FFMContext *ffm = s->priv_data;
+    ByteIOContext *pb = &s->pb;
+    offset_t pos;
+
+    pos = pos1 + ffm->write_index;
+    if (pos >= ffm->file_size)
+        pos -= (ffm->file_size - FFM_PACKET_SIZE);
+#ifdef DEBUG_SEEK
+    printf("seek to %Lx -> %Lx\n", pos1, pos);
+#endif
+    url_fseek(pb, pos, SEEK_SET);
+}
+
+static INT64 get_pts(AVFormatContext *s, offset_t pos)
+{
+    ByteIOContext *pb = &s->pb;
+    INT64 pts;
+
+    ffm_seek1(s, pos); 
+    url_fskip(pb, 4);
+    pts = get_be64(pb);
+#ifdef DEBUG_SEEK
+    printf("pts=%0.6f\n", pts / 1000000.0);
+#endif
+    return pts;
+}
+
+/* seek to a given time in the file. The file read pointer is
+   positionned at or before pts. XXX: the following code is quite
+   approximative */
+static int ffm_seek(AVFormatContext *s, INT64 wanted_pts)
+{
+    FFMContext *ffm = s->priv_data;
+    offset_t pos_min, pos_max, pos;
+    INT64 pts_min, pts_max, pts;
+    double pos1;
+
+#ifdef DEBUG_SEEK
+    printf("wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
+#endif
+    /* find the position using linear interpolation (better than
+       dichotomy in typical cases) */
+    pos_min = 0;
+    pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
+    while (pos_min <= pos_max) {
+        pts_min = get_pts(s, pos_min);
+        pts_max = get_pts(s, pos_max);
+        /* linear interpolation */
+        pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) / 
+            (double)(pts_max - pts_min);
+        pos = (((INT64)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
+        if (pos <= pos_min)
+            pos = pos_min;
+        else if (pos >= pos_max)
+            pos = pos_max;
+        pts = get_pts(s, pos);
+        /* check if we are lucky */
+        if (pts == wanted_pts) {
+            goto found;
+        } else if (pts > wanted_pts) {
+            pos_max = pos - FFM_PACKET_SIZE;
+        } else {
+            pos_min = pos + FFM_PACKET_SIZE;
+        }
+    }
+    pos = pos_min;
+    if (pos > 0)
+        pos -= FFM_PACKET_SIZE;
+ found:
+    ffm_seek1(s, pos);
+    return 0;
+}
+
+offset_t ffm_read_write_index(int fd)
+{
+    UINT8 buf[8];
+    offset_t pos;
+    int i;
+
+    lseek(fd, 8, SEEK_SET);
+    read(fd, buf, 8);
+    pos = 0;
+    for(i=0;i<8;i++) 
+        pos |= buf[i] << (56 - i * 8);
+    return pos;
+}
+
+void ffm_write_write_index(int fd, offset_t pos)
+{
+    UINT8 buf[8];
+    int i;
+
+    for(i=0;i<8;i++) 
+        buf[i] = (pos >> (56 - i * 8)) & 0xff;
+    lseek(fd, 8, SEEK_SET);
+    write(fd, buf, 8);
+}
+
+void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
+{
+    FFMContext *ffm = s->priv_data;
+    ffm->write_index = pos;
+    ffm->file_size = file_size;
+}
+
+static int ffm_read_close(AVFormatContext *s)
+{
+    AVStream *st;
+    int i;
+
+    for(i=0;i<s->nb_streams;i++) {
+        st = s->streams[i];
+        free(st->priv_data);
+    }
+    free(s->priv_data);
+    return 0;
+}
+
+AVFormat ffm_format = {
+    "ffm",
+    "ffm format",
+    "",
+    "ffm",
+    /* not really used */
+    CODEC_ID_MP2,
+    CODEC_ID_MPEG1VIDEO,
+    ffm_write_header,
+    ffm_write_packet,
+    ffm_write_trailer,
+    ffm_read_header,
+    ffm_read_packet,
+    ffm_read_close,
+    ffm_seek,
+};