vcodecs.c File Reference

#include "asterisk.h"
#include "console_video.h"
#include "asterisk/frame.h"
#include "asterisk/utils.h"

Include dependency graph for vcodecs.c:

Go to the source code of this file.

Data Structures
struct	_cm
struct	video_codec_desc
struct	video_dec_desc

Macros
#define	H261_MIN_LEN   10
#define	H263_MIN_LEN   6
#define	HAVE_NAL(x)   (x[-4] == 0 && x[-3] == 0 && x[-2] == 0 && x[-1] == 1)
#define	N_DEC_IN   3 /* number of incoming buffers */

Typedefs
typedef int(*	decoder_decap_f) (struct fbuf_t *b, uint8_t *data, int len)
	extract the bitstream from RTP frames and store in the fbuf. return 0 if ok, 1 on error More...
typedef int(*	decoder_decode_f) (struct video_dec_desc *v, struct fbuf_t *b)
	actually call the decoder More...
typedef int(*	decoder_init_f) (AVCodecContext *enc_ctx)
	inizialize the decoder More...
typedef struct ast_frame *(*	encoder_encap_f) (struct fbuf_t *, int mtu, struct ast_frame **tail)
	encapsulate the bistream in RTP frames More...
typedef int(*	encoder_encode_f) (struct video_out_desc *v)
	actually call the encoder More...
typedef int(*	encoder_init_f) (AVCodecContext *v)
	initialize the encoder More...

Functions
static struct ast_frame *	create_video_frame (uint8_t *start, uint8_t *end, int format, int head, struct ast_frame *prev)
static struct video_dec_desc *	dec_init (uint32_t the_ast_format)
static struct video_dec_desc *	dec_uninit (struct video_dec_desc *v)
	uninitialize the descriptor for remote video stream More...
static int	fbuf_append (struct fbuf_t *b, uint8_t *src, int len, int sbit, int ebit)
static int	ffmpeg_decode (struct video_dec_desc *v, struct fbuf_t *b)
static int	ffmpeg_encode (struct video_out_desc *v)
static int	h261_decap (struct fbuf_t *b, uint8_t *data, int len)
static int	h261_enc_init (AVCodecContext *enc_ctx)
static struct ast_frame *	h261_encap (struct fbuf_t *b, int mtu, struct ast_frame **tail)
static int	h263_decap (struct fbuf_t *b, uint8_t *data, int len)
static int	h263_enc_init (AVCodecContext *enc_ctx)
static struct ast_frame *	h263_encap (struct fbuf_t *b, int mtu, struct ast_frame **tail)
static int	h263p_decap (struct fbuf_t *b, uint8_t *data, int len)
	extract the bitstream from the RTP payload. This is format dependent. For h263+, the format is defined in RFC 2429 and basically has a fixed 2-byte header as follows: 5 bits RR reserved, shall be 0 1 bit P indicate a start/end condition, in which case the payload should be prepended by two zero-valued bytes. 1 bit V there is an additional VRC header after this header 6 bits PLEN length in bytes of extra picture header 3 bits PEBIT how many bits to be ignored in the last byte More...
static int	h263p_enc_init (AVCodecContext *enc_ctx)
	initialization of h263p More...
static struct ast_frame *	h263p_encap (struct fbuf_t *b, int mtu, struct ast_frame **tail)
static int	h264_dec_init (AVCodecContext *dec_ctx)
static int	h264_decap (struct fbuf_t *b, uint8_t *data, int len)
static int	h264_enc_init (AVCodecContext *enc_ctx)
static struct ast_frame *	h264_encap (struct fbuf_t *b, int mtu, struct ast_frame **tail)
static struct video_codec_desc *	map_video_codec (int fmt)
static enum CodecID	map_video_format (uint32_t ast_format, int rw)
	map an asterisk format into an ffmpeg one More...
static int	mpeg4_decap (struct fbuf_t *b, uint8_t *data, int len)
static int	mpeg4_decode (struct video_dec_desc *v, struct fbuf_t *b)
static int	mpeg4_enc_init (AVCodecContext *enc_ctx)
static struct ast_frame *	mpeg4_encap (struct fbuf_t *b, int mtu, struct ast_frame **tail)

Variables
static struct video_codec_desc	h261_codec
static struct video_codec_desc	h263_codec
static struct video_codec_desc	h263p_codec
static struct video_codec_desc	h264_codec
static struct video_codec_desc	mpeg4_codec
static const struct video_codec_desc *	supported_codecs []
static const struct _cm	video_formats []

Macro Definition Documentation

H261_MIN_LEN

#define H261_MIN_LEN   10

H263_MIN_LEN

#define H263_MIN_LEN   6

HAVE_NAL

#define HAVE_NAL

(

x

)

(x[-4] == 0 && x[-3] == 0 && x[-2] == 0 && x[-1] == 1)

N_DEC_IN

#define N_DEC_IN   3 /* number of incoming buffers */

Definition at line 92 of file vcodecs.c.

Typedef Documentation

decoder_decap_f

typedef int(* decoder_decap_f) (struct fbuf_t *b, uint8_t *data, int len)

extract the bitstream from RTP frames and store in the fbuf. return 0 if ok, 1 on error

Definition at line 54 of file vcodecs.c.

decoder_decode_f

typedef int(* decoder_decode_f) (struct video_dec_desc *v, struct fbuf_t *b)

actually call the decoder

Definition at line 57 of file vcodecs.c.

decoder_init_f

typedef int(* decoder_init_f) (AVCodecContext *enc_ctx)

inizialize the decoder

Definition at line 49 of file vcodecs.c.

encoder_encap_f

typedef struct ast_frame *(* encoder_encap_f) (struct fbuf_t *, int mtu, struct ast_frame **tail)

encapsulate the bistream in RTP frames

Definition at line 42 of file vcodecs.c.

encoder_encode_f

typedef int(* encoder_encode_f) (struct video_out_desc *v)

actually call the encoder

Definition at line 42 of file vcodecs.c.

encoder_init_f

typedef int(* encoder_init_f) (AVCodecContext *v)

initialize the encoder

Definition at line 39 of file vcodecs.c.

Function Documentation

create_video_frame()

static struct ast_frame * create_video_frame ( uint8_t *  start, uint8_t *  end, int  format, int  head, struct ast_frame *  prev  )

static

Build an ast_frame for a given chunk of data, and link it into the queue, with possibly 'head' bytes at the beginning to fill in some fields later.

Definition at line 228 of file vcodecs.c.

{
    int len = end-start;
    uint8_t *data;
    struct ast_frame *f;
 
    data = ast_calloc(1, len+head);
    f = ast_calloc(1, sizeof(*f));
    if (f == NULL || data == NULL) {
        ast_log(LOG_WARNING, "--- frame error f %p data %p len %d format %d\n",
                f, data, len, format);
        if (f)
            ast_free(f);
        if (data)
            ast_free(data);
        return NULL;
    }
    memcpy(data+head, start, len);
    f->data.ptr = data;
    f->mallocd = AST_MALLOCD_DATA | AST_MALLOCD_HDR;
    //f->has_timing_info = 1;
    //f->ts = ast_tvdiff_ms(ast_tvnow(), out->ts);
    f->datalen = len+head;
    f->frametype = AST_FRAME_VIDEO;
    f->subclass = format;
    f->samples = 0;
    f->offset = 0;
    f->src = "Console";
    f->delivery.tv_sec = 0;
    f->delivery.tv_usec = 0;
    f->seqno = 0;
    AST_LIST_NEXT(f, frame_list) = NULL;
 
    if (prev)
            AST_LIST_NEXT(prev, frame_list) = f;
 
    return f;
}

References ast_calloc, AST_FRAME_VIDEO, ast_free, AST_LIST_NEXT, ast_log, AST_MALLOCD_DATA, AST_MALLOCD_HDR, ast_frame::data, ast_frame::datalen, ast_frame::delivery, end, ast_frame::frametype, len(), LOG_WARNING, ast_frame::mallocd, NULL, ast_frame::offset, ast_frame::ptr, ast_frame::samples, ast_frame::seqno, ast_frame::src, and ast_frame::subclass.

Referenced by h261_encap(), h263_encap(), h263p_encap(), h264_encap(), and mpeg4_encap().

dec_init()

static struct video_dec_desc * dec_init ( uint32_t  the_ast_format )

static

Definition at line 1204 of file vcodecs.c.

{
    enum CodecID codec;
    struct video_dec_desc *v = ast_calloc(1, sizeof(*v));
    if (v == NULL)
        return NULL;
 
    v->discard = 1;
 
    v->d_callbacks = map_video_codec(the_ast_format);
    if (v->d_callbacks == NULL) {
        ast_log(LOG_WARNING, "cannot find video codec, drop input 0x%x\n", the_ast_format);
        return dec_uninit(v);
    }
 
    codec = map_video_format(v->d_callbacks->format, CM_RD);
 
    v->codec = avcodec_find_decoder(codec);
    if (!v->codec) {
        ast_log(LOG_WARNING, "Unable to find the decoder for format %d\n", codec);
        return dec_uninit(v);
    }
    /*
     * Initialize the codec context.
     */
    v->dec_ctx = avcodec_alloc_context();
    if (!v->dec_ctx) {
        ast_log(LOG_WARNING, "Cannot allocate the decoder context\n");
        return dec_uninit(v);
    }
    /* XXX call dec_init() ? */
    if (avcodec_open(v->dec_ctx, v->codec) < 0) {
        ast_log(LOG_WARNING, "Cannot open the decoder context\n");
        av_free(v->dec_ctx);
        v->dec_ctx = NULL;
        return dec_uninit(v);
    }
 
    v->parser = av_parser_init(codec);
    if (!v->parser) {
        ast_log(LOG_WARNING, "Cannot initialize the decoder parser\n");
        return dec_uninit(v);
    }
 
    v->d_frame = avcodec_alloc_frame();
    if (!v->d_frame) {
        ast_log(LOG_WARNING, "Cannot allocate decoding video frame\n");
        return dec_uninit(v);
    }
        v->dec_in_cur = &v->dec_in[0];  /* buffer for incoming frames */
        v->dec_in_dpy = NULL;      /* nothing to display */
 
    return v;   /* ok */
}

References ast_calloc, ast_log, video_dec_desc::codec, video_dec_desc::d_callbacks, video_dec_desc::d_frame, video_dec_desc::dec_ctx, video_dec_desc::dec_in, video_dec_desc::dec_in_cur, video_dec_desc::dec_in_dpy, dec_uninit(), video_dec_desc::discard, video_codec_desc::format, LOG_WARNING, map_video_codec(), map_video_format(), NULL, and video_dec_desc::parser.

dec_uninit()

static struct video_dec_desc * dec_uninit ( struct video_dec_desc *  v )

static

uninitialize the descriptor for remote video stream

Definition at line 1172 of file vcodecs.c.

{
    int i;
 
    if (v == NULL)      /* not initialized yet */
        return NULL;
    if (v->parser) {
        av_parser_close(v->parser);
        v->parser = NULL;
    }
    if (v->dec_ctx) {
        avcodec_close(v->dec_ctx);
        av_free(v->dec_ctx);
        v->dec_ctx = NULL;
    }
    if (v->d_frame) {
        av_free(v->d_frame);
        v->d_frame = NULL;
    }
    v->codec = NULL;    /* only a reference */
    v->d_callbacks = NULL;      /* forget the decoder */
    v->discard = 1;     /* start in discard mode */
    for (i = 0; i < N_DEC_IN; i++)
        fbuf_free(&v->dec_in[i]);
    fbuf_free(&v->dec_out);
    ast_free(v);
    return NULL;    /* error, in case someone cares */
}

References ast_free, video_dec_desc::codec, video_dec_desc::d_callbacks, video_dec_desc::d_frame, video_dec_desc::dec_ctx, video_dec_desc::dec_in, video_dec_desc::dec_out, video_dec_desc::discard, fbuf_free(), N_DEC_IN, NULL, and video_dec_desc::parser.

Referenced by dec_init().

fbuf_append()

static int fbuf_append ( struct fbuf_t *  b, uint8_t *  src, int  len, int  sbit, int  ebit  )

static

Definition at line 273 of file vcodecs.c.

{
    /*
     * Allocate buffer. ffmpeg wants an extra FF_INPUT_BUFFER_PADDING_SIZE,
     * and also wants 0 as a buffer terminator to prevent trouble.
     */
    int need = len + FF_INPUT_BUFFER_PADDING_SIZE;
    int i;
    uint8_t *dst, mask;
 
    if (b->data == NULL) {
        b->size = need;
        b->used = 0;
        b->ebit = 0;
        b->data = ast_calloc(1, b->size);
    } else if (b->used + need > b->size) {
        b->size = b->used + need;
        b->data = ast_realloc(b->data, b->size);
    }
    if (b->data == NULL) {
        ast_log(LOG_WARNING, "alloc failure for %d, discard\n",
            b->size);
        return 1;
    }
    if (b->used == 0 && b->ebit != 0) {
        ast_log(LOG_WARNING, "ebit not reset at start\n");
        b->ebit = 0;
    }
    dst = b->data + b->used;
    i = b->ebit + sbit; /* bits to ignore around */
    if (i == 0) {   /* easy case, just append */
        /* do everything in the common block */
    } else if (i == 8) { /* easy too, just handle the overlap byte */
        mask = (1 << b->ebit) - 1;
        /* update the last byte in the buffer */
        dst[-1] &= ~mask;   /* clear bits to ignore */
        dst[-1] |= (*src & mask);   /* append new bits */
        src += 1;   /* skip and prepare for common block */
        len --;
    } else {    /* must shift the new block, not done yet */
        ast_log(LOG_WARNING, "must handle shift %d %d at %d\n",
            b->ebit, sbit, b->used);
        return 1;
    }
    memcpy(dst, src, len);
    b->used += len;
    b->ebit = ebit;
    b->data[b->used] = 0;   /* padding */
    return 0;
}

References ast_calloc, ast_log, ast_realloc, b, len(), LOG_WARNING, NULL, and ast_frame::src.

Referenced by h261_decap(), h263_decap(), h263p_decap(), h264_decap(), and mpeg4_decap().

ffmpeg_decode()

static int ffmpeg_decode ( struct video_dec_desc *  v, struct fbuf_t *  b  )

static

Definition at line 482 of file vcodecs.c.

{
    uint8_t *src = b->data;
    int srclen = b->used;
    int full_frame = 0;
 
    if (srclen == 0)    /* no data */
        return 0;
    while (srclen) {
        uint8_t *data;
        int datalen, ret;
        int len = av_parser_parse(v->parser, v->dec_ctx, &data, &datalen, src, srclen, 0, 0);
 
        src += len;
        srclen -= len;
        /* The parser might return something it cannot decode, so it skips
         * the block returning no data
         */
        if (data == NULL || datalen == 0)
            continue;
        ret = avcodec_decode_video(v->dec_ctx, v->d_frame, &full_frame, data, datalen);
        if (full_frame == 1)    /* full frame */
            break;
        if (ret < 0) {
            ast_log(LOG_NOTICE, "Error decoding\n");
            break;
        }
    }
    if (srclen != 0)    /* update b with leftover data */
        memmove(b->data, src, srclen);
    b->used = srclen;
    b->ebit = 0;
    return full_frame;
}

References ast_log, b, video_dec_desc::d_frame, fbuf_t::data, video_dec_desc::dec_ctx, len(), LOG_NOTICE, NULL, and video_dec_desc::parser.

ffmpeg_encode()

static int ffmpeg_encode ( struct video_out_desc *  v )

static

Definition at line 461 of file vcodecs.c.

{
    struct fbuf_t *b = &v->enc_out;
    int i;
 
    b->used = avcodec_encode_video(v->enc_ctx, b->data, b->size, v->enc_in_frame);
    i = avcodec_encode_video(v->enc_ctx, b->data + b->used, b->size - b->used, NULL); /* delayed frames ? */
    if (i > 0) {
        ast_log(LOG_WARNING, "have %d more bytes\n", i);
        b->used += i;
    }
    return 0;
}

References ast_log, b, LOG_WARNING, and NULL.

h261_decap()

static int h261_decap ( struct fbuf_t *  b, uint8_t *  data, int  len  )

static

Definition at line 827 of file vcodecs.c.

{
    int ebit, sbit;
 
    if (len < 8) {
        ast_log(LOG_WARNING, "invalid framesize %d\n", len);
        return 1;
    }
    sbit = (data[0] >> 5) & 7;
    ebit = (data[0] >> 2) & 7;
    len -= 4;
    data += 4;
    return fbuf_append(b, data, len, sbit, ebit);
}

References ast_log, b, ast_frame::data, fbuf_append(), len(), and LOG_WARNING.

h261_enc_init()

static int h261_enc_init ( AVCodecContext *  enc_ctx )

static

Definition at line 702 of file vcodecs.c.

{
    /* It is important to set rtp_payload_size = 0, otherwise
     * ffmpeg in h261 mode will produce output that it cannot parse.
     * Also try to send I frames more frequently than with other codecs.
     */
    enc_ctx->rtp_payload_size = 0; /* important - ffmpeg fails otherwise */
 
    return 0;
}

h261_encap()

static struct ast_frame * h261_encap ( struct fbuf_t *  b, int  mtu, struct ast_frame **  tail  )

static

Definition at line 729 of file vcodecs.c.

{
    uint8_t *d = b->data;
    int start = 0, i, len = b->used;
    struct ast_frame *f, *cur = NULL, *first = NULL;
    const int pheader_len = 4;
    uint8_t h261_hdr[4];
    uint8_t *h = h261_hdr;  /* shorthand */
    int sbit = 0, ebit = 0;
 
#define H261_MIN_LEN 10
    if (len < H261_MIN_LEN) /* unreasonably small */
        return NULL;
 
    memset(h261_hdr, '\0', sizeof(h261_hdr));
 
    /* Similar to the code in h263_encap, but the marker there is longer.
     * Start a few bytes within the bitstream to avoid hitting the marker
     * twice. Note we might access the buffer at len, but this is ok because
     * the caller has it oversized.
     */
    for (i = H261_MIN_LEN, start = 0; start < len - 1; start = i, i += 4) {
#if 0   /* test - disable packetization */
        i = len;    /* wrong... */
#else
        int found = 0, found_ebit = 0;  /* last GBSC position found */
        for (; i < len ; i++) {
            uint8_t x, rpos, lpos;
            if (d[i] != 0)      /* cannot be in a GBSC */
                continue;
            x = d[i+1];
            if (x == 0) /* next is equally good */
                continue;
            /* See if around us we find 15 '0' bits for the GBSC.
             * Look for the first bit set on the right, and then
             * see if we have enough 0 on the left.
             * We are guaranteed to end before rpos == 0
             */
            for (rpos = 0x80, ebit = 7; rpos; ebit--, rpos >>= 1)
                if (x & rpos)   /* found the '1' bit in GBSC */
                    break;
            x = d[i-1];     /* now look behind */
            for (lpos = (rpos >> 1); lpos ; lpos >>= 1)
                if (x & lpos)   /* too early, not a GBSC */
                    break;
            if (lpos)       /* as i said... */
                continue;
            /* now we have a GBSC starting somewhere in d[i-1],
             * but it might be not byte-aligned. Just remember it.
             */
            if (i - start > mtu) /* too large, stop now */
                break;
            found_ebit = ebit;
            found = i;
            i += 4; /* continue forward */
        }
        if (i >= len) { /* trim if we went too forward */
            i = len;
            ebit = 0;   /* hopefully... should ask the bitstream ? */
        }
        if (i - start > mtu && found) {
            /* use the previous GBSC, hope is within the mtu */
            i = found;
            ebit = found_ebit;
        }
#endif /* test */
        if (i - start < 4)  /* XXX too short ? */
            continue;
        /* This frame is up to offset i (not inclusive).
         * We do not split it yet even if larger than MTU.
         */
        f = create_video_frame(d + start, d+i, AST_FORMAT_H261,
                pheader_len, cur);
 
        if (!f)
            break;
        /* recompute header with I=0, V=1 */
        h[0] = ( (sbit & 7) << 5 ) | ( (ebit & 7) << 2 ) | 1;
        memmove(f->data.ptr, h, 4); /* copy the h261 header */
        if (ebit)   /* not aligned, restart from previous byte */
            i--;
        sbit = (8 - ebit) & 7;
        ebit = 0;
        if (!cur)
            first = f;
        cur = f;
    }
    if (cur)
        cur->subclass |= 1; // RTP Marker
 
    *tail = cur;
    return first;
}

References AST_FORMAT_H261, b, create_video_frame(), d, ast_frame::data, first, H261_MIN_LEN, len(), NULL, ast_frame::ptr, and ast_frame::subclass.

h263_decap()

static int h263_decap ( struct fbuf_t *  b, uint8_t *  data, int  len  )

static

Definition at line 671 of file vcodecs.c.

{
    if (len < 4) {
        ast_log(LOG_WARNING, "invalid framesize %d\n", len);
        return 1;   /* error */
    }
 
    if ( (data[0] & 0x80) == 0) {
        len -= 4;
        data += 4;
    } else {
        ast_log(LOG_WARNING, "unsupported mode 0x%x\n",
            data[0]);
        return 1;
    }
    return fbuf_append(b, data, len, 0, 0); /* XXX no bit alignment support yet */
}

References ast_log, b, ast_frame::data, fbuf_append(), len(), and LOG_WARNING.

h263_enc_init()

static int h263_enc_init ( AVCodecContext *  enc_ctx )

static

Definition at line 530 of file vcodecs.c.

{
    /* XXX check whether these are supported */
    enc_ctx->flags |= CODEC_FLAG_H263P_UMV;
    enc_ctx->flags |= CODEC_FLAG_H263P_AIC;
    enc_ctx->flags |= CODEC_FLAG_H263P_SLICE_STRUCT;
    enc_ctx->flags |= CODEC_FLAG_AC_PRED;
 
    return 0;
}

h263_encap()

static struct ast_frame * h263_encap ( struct fbuf_t *  b, int  mtu, struct ast_frame **  tail  )

static

Definition at line 575 of file vcodecs.c.

{
    uint8_t *d = b->data;
    int start = 0, i, len = b->used;
    struct ast_frame *f, *cur = NULL, *first = NULL;
    const int pheader_len = 4;  /* Use RFC-2190 Mode A */
    uint8_t h263_hdr[12];   /* worst case, room for a type c header */
    uint8_t *h = h263_hdr;  /* shorthand */
 
#define H263_MIN_LEN    6
    if (len < H263_MIN_LEN) /* unreasonably small */
        return NULL;
 
    memset(h263_hdr, '\0', sizeof(h263_hdr));
    /* Now set the header bytes. Only type A by now,
     * and h[0] = h[2] = h[3] = 0 by default.
     * PTYPE starts 30 bits in the picture, so the first useful
     * bit for us is bit 36 i.e. within d[4] (0 is the msbit).
     * SRC = d[4] & 0x1c goes into data[1] & 0xe0
     * I   = d[4] & 0x02 goes into data[1] & 0x10
     * U   = d[4] & 0x01 goes into data[1] & 0x08
     * S   = d[5] & 0x80 goes into data[1] & 0x04
     * A   = d[5] & 0x40 goes into data[1] & 0x02
     * R   = 0           goes into data[1] & 0x01
     * Optimizing it, we have
     */
    h[1] = ( (d[4] & 0x1f) << 3 ) | /* SRC, I, U */
        ( (d[5] & 0xc0) >> 5 );     /* S, A, R */
 
    /* now look for the next PSC or GOB header. First try to hit
     * a '0' byte then look around for the 0000 0000 0000 0000 1 pattern
     * which is both in the PSC and the GBSC.
     */
    for (i = H263_MIN_LEN, start = 0; start < len; start = i, i += 3) {
        //ast_log(LOG_WARNING, "search at %d of %d/%d\n", i, start, len);
        for (; i < len ; i++) {
            uint8_t x, rpos, lpos;
            int rpos_i; /* index corresponding to rpos */
            if (d[i] != 0)      /* cannot be in a GBSC */
                continue;
            if (i > len - 1)
                break;
            x = d[i+1];
            if (x == 0) /* next is equally good */
                continue;
            /* see if around us we can make 16 '0' bits for the GBSC.
             * Look for the first bit set on the right, and then
             * see if we have enough 0 on the left.
             * We are guaranteed to end before rpos == 0
             */
            for (rpos = 0x80, rpos_i = 8; rpos; rpos >>= 1, rpos_i--)
                if (x & rpos)   /* found the '1' bit in GBSC */
                    break;
            x = d[i-1];     /* now look behind */
            for (lpos = rpos; lpos ; lpos >>= 1)
                if (x & lpos)   /* too early, not a GBSC */
                    break;
            if (lpos)       /* as i said... */
                continue;
            /* now we have a GBSC starting somewhere in d[i-1],
             * but it might be not byte-aligned
             */
            if (rpos == 0x80) { /* lucky case */
                i = i - 1;
            } else {    /* XXX to be completed */
                ast_log(LOG_WARNING, "unaligned GBSC 0x%x %d\n",
                    rpos, rpos_i);
            }
            break;
        }
        /* This frame is up to offset i (not inclusive).
         * We do not split it yet even if larger than MTU.
         */
        f = create_video_frame(d + start, d+i, AST_FORMAT_H263,
                pheader_len, cur);
 
        if (!f)
            break;
        memmove(f->data.ptr, h, 4); /* copy the h263 header */
        /* XXX to do: if not aligned, fix sbit and ebit,
         * then move i back by 1 for the next frame
         */
        if (!cur)
            first = f;
        cur = f;
    }
 
    if (cur)
        cur->subclass |= 1; // RTP Marker
 
    *tail = cur;
    return first;
}

References AST_FORMAT_H263, ast_log, b, create_video_frame(), d, ast_frame::data, first, H263_MIN_LEN, len(), LOG_WARNING, NULL, ast_frame::ptr, and ast_frame::subclass.

h263p_decap()

static int h263p_decap ( struct fbuf_t *  b, uint8_t *  data, int  len  )

static

extract the bitstream from the RTP payload. This is format dependent. For h263+, the format is defined in RFC 2429 and basically has a fixed 2-byte header as follows: 5 bits RR reserved, shall be 0 1 bit P indicate a start/end condition, in which case the payload should be prepended by two zero-valued bytes. 1 bit V there is an additional VRC header after this header 6 bits PLEN length in bytes of extra picture header 3 bits PEBIT how many bits to be ignored in the last byte

XXX the code below is not complete.

Definition at line 433 of file vcodecs.c.

{
    int PLEN;
 
    if (len < 2) {
        ast_log(LOG_WARNING, "invalid framesize %d\n", len);
        return 1;
    }
    PLEN = ( (data[0] & 1) << 5 ) | ( (data[1] & 0xf8) >> 3);
 
    if (PLEN > 0) {
        data += PLEN;
        len -= PLEN;
    }
    if (data[0] & 4)    /* bit P */
        data[0] = data[1] = 0;
    else {
        data += 2;
        len -= 2;
    }
    return fbuf_append(b, data, len, 0, 0); /* ignore trail bits */
}

References ast_log, b, ast_frame::data, fbuf_append(), len(), and LOG_WARNING.

h263p_enc_init()

static int h263p_enc_init ( AVCodecContext *  enc_ctx )

static

initialization of h263p

Definition at line 335 of file vcodecs.c.

{
    /* modes supported are
    - Unrestricted Motion Vector (annex D)
    - Advanced Prediction (annex F)
    - Advanced Intra Coding (annex I)
    - Deblocking Filter (annex J)
    - Slice Structure (annex K)
    - Alternative Inter VLC (annex S)
    - Modified Quantization (annex T)
    */
    enc_ctx->flags |=CODEC_FLAG_H263P_UMV; /* annex D */
    enc_ctx->flags |=CODEC_FLAG_AC_PRED; /* annex f ? */
    enc_ctx->flags |=CODEC_FLAG_H263P_SLICE_STRUCT; /* annex k */
    enc_ctx->flags |= CODEC_FLAG_H263P_AIC; /* annex I */
 
    return 0;
}

h263p_encap()

static struct ast_frame * h263p_encap ( struct fbuf_t *  b, int  mtu, struct ast_frame **  tail  )

static

Definition at line 360 of file vcodecs.c.

{
    struct ast_frame *cur = NULL, *first = NULL;
    uint8_t *d = b->data;
    int len = b->used;
    int l = len; /* size of the current fragment. If 0, must look for a psc */
 
    for (;len > 0; len -= l, d += l) {
        uint8_t *data;
        struct ast_frame *f;
        int i, h;
 
        if (len >= 3 && d[0] == 0 && d[1] == 0 && d[2] >= 0x80) {
            /* we are starting a new block, so look for a PSC. */
            for (i = 3; i < len - 3; i++) {
                if (d[i] == 0 && d[i+1] == 0 && d[i+2] >= 0x80) {
                    l = i;
                    break;
                }
            }
        }
        if (l > mtu || l > len) { /* psc not found, split */
            l = MIN(len, mtu);
        }
        if (l < 1 || l > mtu) {
            ast_log(LOG_WARNING, "--- frame error l %d\n", l);
            break;
        }
 
        if (d[0] == 0 && d[1] == 0) { /* we start with a psc */
            h = 0;
        } else { /* no psc, create a header */
            h = 2;
        }
 
        f = create_video_frame(d, d+l, AST_FORMAT_H263_PLUS, h, cur);
        if (!f)
            break;
 
        data = f->data.ptr;
        if (h == 0) {   /* we start with a psc */
            data[0] |= 0x04;    // set P == 1, and we are done
        } else {    /* no psc, create a header */
            data[0] = data[1] = 0;  // P == 0
        }
 
        if (!cur)
            first = f;
        cur = f;
    }
 
    if (cur)
        cur->subclass |= 1; // RTP Marker
 
    *tail = cur;    /* end of the list */
    return first;
}

References ast_log, b, create_video_frame(), d, ast_frame::data, first, len(), LOG_WARNING, MIN, NULL, ast_frame::ptr, and ast_frame::subclass.

h264_dec_init()

static int h264_dec_init ( AVCodecContext *  dec_ctx )

static

Definition at line 938 of file vcodecs.c.

{
    dec_ctx->flags |= CODEC_FLAG_TRUNCATED;
 
    return 0;
}

h264_decap()

static int h264_decap ( struct fbuf_t *  b, uint8_t *  data, int  len  )

static

Definition at line 1046 of file vcodecs.c.

{
    /* Start Code Prefix (Annex B in specification) */
    uint8_t scp[] = { 0x00, 0x00, 0x00, 0x01 };
    int retval = 0;
    int type, ofs = 0;
 
    if (len < 2) {
        ast_log(LOG_WARNING, "--- invalid len %d\n", len);
        return 1;
    }
    /* first of all, check if the packet has F == 0 */
    if (data[0] & 0x80) {
        ast_log(LOG_WARNING, "--- forbidden packet; nal: %02hhx\n",
            data[0]);
        return 1;
    }
 
    type = data[0] & 0x1f;
    switch (type) {
    case 0:
    case 31:
        ast_log(LOG_WARNING, "--- invalid type: %d\n", type);
        return 1;
    case 24:
    case 25:
    case 26:
    case 27:
    case 29:
        ast_log(LOG_WARNING, "--- encapsulation not supported : %d\n", type);
        return 1;
    case 28:    /* FU-A Unit */
        if (data[1] & 0x80) { // S == 1, import F and NRI from next
            data[1] &= 0x1f;    /* preserve type */
            data[1] |= (data[0] & 0xe0);    /* import F & NRI */
            retval = fbuf_append(b, scp, sizeof(scp), 0, 0);
            ofs = 1;
        } else {
            ofs = 2;
        }
        break;
    default:    /* From 1 to 23 (Single NAL Unit) */
        retval = fbuf_append(b, scp, sizeof(scp), 0, 0);
    }
    if (!retval)
        retval = fbuf_append(b, data + ofs, len - ofs, 0, 0);
    if (retval)
        ast_log(LOG_WARNING, "result %d\n", retval);
    return retval;
}

References ast_log, b, ast_frame::data, fbuf_append(), len(), LOG_WARNING, retval, and type.

h264_enc_init()

static int h264_enc_init ( AVCodecContext *  enc_ctx )

static

Definition at line 926 of file vcodecs.c.

{
    enc_ctx->flags |= CODEC_FLAG_TRUNCATED;
    //enc_ctx->flags |= CODEC_FLAG_GLOBAL_HEADER;
    //enc_ctx->flags2 |= CODEC_FLAG2_FASTPSKIP;
    /* TODO: Maybe we need to add some other flags */
    enc_ctx->rtp_mode = 0;
    enc_ctx->rtp_payload_size = 0;
    enc_ctx->bit_rate_tolerance = enc_ctx->bit_rate;
    return 0;
}

h264_encap()

static struct ast_frame * h264_encap ( struct fbuf_t *  b, int  mtu, struct ast_frame **  tail  )

static

Definition at line 959 of file vcodecs.c.

{
    struct ast_frame *f = NULL, *cur = NULL, *first = NULL;
    uint8_t *d, *start = b->data;
    uint8_t *end = start + b->used;
 
    /* Search the first start code prefix - ITU-T H.264 sec. B.2,
     * and move start right after that, on the NAL header byte.
     */
#define HAVE_NAL(x) (x[-4] == 0 && x[-3] == 0 && x[-2] == 0 && x[-1] == 1)
    for (start += 4; start < end; start++) {
        int ty = start[0] & 0x1f;
        if (HAVE_NAL(start) && ty != 0 && ty != 31)
            break;
    }
    /* if not found, or too short, we just skip the next loop and are done. */
 
    /* Here follows the main loop to create frames. Search subsequent start
     * codes, and then possibly fragment the unit into smaller fragments.
     */
   for (;start < end - 4; start = d) {
    int size;       /* size of current block */
    uint8_t hdr[2];     /* add-on header when fragmenting */
    int ty = 0;
 
    /* now search next nal */
    for (d = start + 4; d < end; d++) {
        ty = d[0] & 0x1f;
        if (HAVE_NAL(d))
            break;  /* found NAL */
    }
    /* have a block to send. d past the start code unless we overflow */
    if (d >= end) { /* NAL not found */
        d = end + 4;
    } else if (ty == 0 || ty == 31) { /* found but invalid type, skip */
        ast_log(LOG_WARNING, "skip invalid nal type %d at %d of %d\n",
            ty, d - (uint8_t *)b->data, b->used);
        continue;
    }
 
    size = d - start - 4;   /* don't count the end */
 
    if (size < mtu) {   // test - don't fragment
        // Single NAL Unit
        f = create_video_frame(start, d - 4, AST_FORMAT_H264, 0, cur);
        if (!f)
            break;
        if (!first)
            first = f;
 
        cur = f;
        continue;
    }
 
    // Fragmented Unit (Mode A: no DON, very weak)
    hdr[0] = (*start & 0xe0) | 28;  /* mark as a fragmentation unit */
    hdr[1] = (*start++ & 0x1f) | 0x80 ; /* keep type and set START bit */
    size--;     /* skip the NAL header */
    while (size) {
        uint8_t *data;
        int frag_size = MIN(size, mtu);
 
        f = create_video_frame(start, start+frag_size, AST_FORMAT_H264, 2, cur);
        if (!f)
            break;
        size -= frag_size;  /* skip this data block */
        start += frag_size;
 
        data = f->data.ptr;
        data[0] = hdr[0];
        data[1] = hdr[1] | (size == 0 ? 0x40 : 0);  /* end bit if we are done */
        hdr[1] &= ~0x80;    /* clear start bit for subsequent frames */
        if (!first)
            first = f;
        cur = f;
    }
    }
 
    if (cur)
        cur->subclass |= 1;     // RTP Marker
 
    *tail = cur;
 
    return first;
}

References AST_FORMAT_H264, ast_log, b, create_video_frame(), d, ast_frame::data, end, first, HAVE_NAL, LOG_WARNING, MIN, NULL, ast_frame::ptr, and ast_frame::subclass.

map_video_codec()

static struct video_codec_desc * map_video_codec ( int  fmt )

static

Definition at line 1158 of file vcodecs.c.

{
    int i;
 
    for (i = 0; supported_codecs[i]; i++)
        if (fmt == supported_codecs[i]->format) {
            ast_log(LOG_WARNING, "using %s for format 0x%x\n",
                supported_codecs[i]->name, fmt);
            return supported_codecs[i];
        }
    return NULL;
}

References ast_log, video_codec_desc::format, LOG_WARNING, name, NULL, and supported_codecs.

Referenced by dec_init().

map_video_format()

static enum CodecID map_video_format ( uint32_t  ast_format, int  rw  )

static

map an asterisk format into an ffmpeg one

Definition at line 1133 of file vcodecs.c.

{
    struct _cm *i;
 
    for (i = video_formats; i->ast_format != 0; i++)
        if (ast_format & i->ast_format && rw & i->rw) {
            return i->codec;
        }
    return CODEC_ID_NONE;
}

References _cm::ast_format, _cm::codec, _cm::rw, and video_formats.

Referenced by dec_init().

mpeg4_decap()

static int mpeg4_decap ( struct fbuf_t *  b, uint8_t *  data, int  len  )

static

Definition at line 893 of file vcodecs.c.

{
    return fbuf_append(b, data, len, 0, 0);
}

References b, ast_frame::data, fbuf_append(), and len().

mpeg4_decode()

static int mpeg4_decode ( struct video_dec_desc *  v, struct fbuf_t *  b  )

static

Definition at line 898 of file vcodecs.c.

{
    int full_frame = 0, datalen = b->used;
    int ret = avcodec_decode_video(v->dec_ctx, v->d_frame, &full_frame,
        b->data, datalen);
    if (ret < 0) {
        ast_log(LOG_NOTICE, "Error decoding\n");
        ret = datalen; /* assume we used everything. */
    }
    datalen -= ret;
    if (datalen > 0)    /* update b with leftover bytes */
        memmove(b->data, b->data + ret, datalen);
    b->used = datalen;
    b->ebit = 0;
    return full_frame;
}

References ast_log, b, video_dec_desc::d_frame, ast_frame::datalen, video_dec_desc::dec_ctx, and LOG_NOTICE.

mpeg4_enc_init()

static int mpeg4_enc_init ( AVCodecContext *  enc_ctx )

static

Definition at line 854 of file vcodecs.c.

{
#if 0
    //enc_ctx->flags |= CODEC_FLAG_LOW_DELAY; /*don't use b frames ?*/
    enc_ctx->flags |= CODEC_FLAG_AC_PRED;
    enc_ctx->flags |= CODEC_FLAG_H263P_UMV;
    enc_ctx->flags |= CODEC_FLAG_QPEL;
    enc_ctx->flags |= CODEC_FLAG_4MV;
    enc_ctx->flags |= CODEC_FLAG_GMC;
    enc_ctx->flags |= CODEC_FLAG_LOOP_FILTER;
    enc_ctx->flags |= CODEC_FLAG_H263P_SLICE_STRUCT;
#endif
    enc_ctx->rtp_payload_size = 0; /* important - ffmpeg fails otherwise */
    return 0;
}

mpeg4_encap()

static struct ast_frame * mpeg4_encap ( struct fbuf_t *  b, int  mtu, struct ast_frame **  tail  )

static

Definition at line 871 of file vcodecs.c.

{
    struct ast_frame *f, *cur = NULL, *first = NULL;
    uint8_t *d = b->data;
    uint8_t *end = d + b->used;
    int len;
 
    for (;d < end; d += len, cur = f) {
        len = MIN(mtu, end - d);
        f = create_video_frame(d, d + len, AST_FORMAT_MP4_VIDEO, 0, cur);
        if (!f)
            break;
        if (!first)
            first = f;
    }
    if (cur)
        cur->subclass |= 1;
    *tail = cur;
    return first;
}

References b, create_video_frame(), d, end, first, len(), MIN, NULL, and ast_frame::subclass.

Variable Documentation

h261_codec

struct video_codec_desc h261_codec

static

Definition at line 842 of file vcodecs.c.

h263_codec

struct video_codec_desc h263_codec

static

Definition at line 689 of file vcodecs.c.

h263p_codec

struct video_codec_desc h263p_codec

static

Definition at line 517 of file vcodecs.c.

h264_codec

struct video_codec_desc h264_codec

static

Definition at line 1097 of file vcodecs.c.

mpeg4_codec

struct video_codec_desc mpeg4_codec

static

Definition at line 915 of file vcodecs.c.

supported_codecs

const struct video_codec_desc* supported_codecs[]

static

Definition at line 1145 of file vcodecs.c.

Referenced by map_video_codec().

video_formats

const struct _cm video_formats[]

static

Definition at line 1120 of file vcodecs.c.

Referenced by map_video_format().