diff options
Diffstat (limited to 'modules/avcodec/h263.c')
| -rw-r--r-- | modules/avcodec/h263.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/modules/avcodec/h263.c b/modules/avcodec/h263.c new file mode 100644 index 0000000..7e29ecd --- /dev/null +++ b/modules/avcodec/h263.c @@ -0,0 +1,176 @@ +/** + * @file h263.c H.263 video codec (RFC 4629) + * + * Copyright (C) 2010 Creytiv.com + */ +#include <re.h> +#include <rem.h> +#include <baresip.h> +#include <libavcodec/avcodec.h> +#ifdef USE_X264 +#include <x264.h> +#endif +#include "h26x.h" +#include "avcodec.h" + + +int h263_hdr_encode(const struct h263_hdr *hdr, struct mbuf *mb) +{ + uint32_t v; /* host byte order */ + + v = hdr->f<<31 | hdr->p<<30 | hdr->sbit<<27 | hdr->ebit<<24; + v |= hdr->src<<21 | hdr->i<<20 | hdr->u<<19 | hdr->s<<18 | hdr->a<<17; + v |= hdr->r<<13 | hdr->dbq<<11 | hdr->trb<<8 | hdr->tr<<0; + + return mbuf_write_u32(mb, htonl(v)); +} + + +enum h263_mode h263_hdr_mode(const struct h263_hdr *hdr) +{ + if (!hdr->f) { + return H263_MODE_A; + } + else { + if (!hdr->p) + return H263_MODE_B; + else + return H263_MODE_C; + } +} + + +int h263_hdr_decode(struct h263_hdr *hdr, struct mbuf *mb) +{ + uint32_t v; + + if (!hdr) + return EINVAL; + if (mbuf_get_left(mb) < H263_HDR_SIZE_MODEA) + return EBADMSG; + + v = ntohl(mbuf_read_u32(mb)); + + /* Common */ + hdr->f = v>>31 & 0x1; + hdr->p = v>>30 & 0x1; + hdr->sbit = v>>27 & 0x7; + hdr->ebit = v>>24 & 0x7; + hdr->src = v>>21 & 0x7; + + switch (h263_hdr_mode(hdr)) { + + case H263_MODE_A: + hdr->i = v>>20 & 0x1; + hdr->u = v>>19 & 0x1; + hdr->s = v>>18 & 0x1; + hdr->a = v>>17 & 0x1; + hdr->r = v>>13 & 0xf; + hdr->dbq = v>>11 & 0x3; + hdr->trb = v>>8 & 0x7; + hdr->tr = v>>0 & 0xff; + break; + + case H263_MODE_B: + hdr->quant = v>>16 & 0x1f; + hdr->gobn = v>>11 & 0x1f; + hdr->mba = v>>2 & 0x1ff; + + if (mbuf_get_left(mb) < 4) + return EBADMSG; + + v = ntohl(mbuf_read_u32(mb)); + + hdr->i = v>>31 & 0x1; + hdr->u = v>>30 & 0x1; + hdr->s = v>>29 & 0x1; + hdr->a = v>>28 & 0x1; + hdr->hmv1 = v>>21 & 0x7f; + hdr->vmv1 = v>>14 & 0x7f; + hdr->hmv2 = v>>7 & 0x7f; + hdr->vmv2 = v>>0 & 0x7f; + break; + + case H263_MODE_C: + /* NOTE: Mode C is optional, only parts decoded */ + if (mbuf_get_left(mb) < 8) + return EBADMSG; + + v = ntohl(mbuf_read_u32(mb)); + hdr->i = v>>31 & 0x1; + hdr->u = v>>30 & 0x1; + hdr->s = v>>29 & 0x1; + hdr->a = v>>28 & 0x1; + + (void)mbuf_read_u32(mb); /* ignore */ + break; + } + + return 0; +} + + +/** Find PSC (Picture Start Code) in bit-stream */ +const uint8_t *h263_strm_find_psc(const uint8_t *p, uint32_t size) +{ + const uint8_t *end = p + size - 1; + + for (; p < end; p++) { + if (p[0] == 0x00 && p[1] == 0x00) + return p; + } + + return NULL; +} + + +int h263_strm_decode(struct h263_strm *s, struct mbuf *mb) +{ + const uint8_t *p; + + if (mbuf_get_left(mb) < 6) + return EINVAL; + + p = mbuf_buf(mb); + + s->psc[0] = p[0]; + s->psc[1] = p[1]; + + s->temp_ref = (p[2]<<6 & 0xc0) | (p[3]>>2 & 0x3f); + + s->split_scr = p[4]>>7 & 0x1; + s->doc_camera = p[4]>>6 & 0x1; + s->pic_frz_rel = p[4]>>5 & 0x1; + s->src_fmt = p[4]>>2 & 0x7; + s->pic_type = p[4]>>1 & 0x1; + s->umv = p[4]>>0 & 0x1; + + s->sac = p[5]>>7 & 0x1; + s->apm = p[5]>>6 & 0x1; + s->pb = p[5]>>5 & 0x1; + s->pquant = p[5]>>0 & 0x1f; + + s->cpm = p[6]>>7 & 0x1; + s->pei = p[6]>>6 & 0x1; + + return 0; +} + + +/** Copy H.263 bit-stream to H.263 RTP payload header */ +void h263_hdr_copy_strm(struct h263_hdr *hdr, const struct h263_strm *s) +{ + hdr->f = 0; /* Mode A */ + hdr->p = 0; + hdr->sbit = 0; + hdr->ebit = 0; + hdr->src = s->src_fmt; + hdr->i = s->pic_type; + hdr->u = s->umv; + hdr->s = s->sac; + hdr->a = s->apm; + hdr->r = 0; + hdr->dbq = 0; /* No PB-frames */ + hdr->trb = 0; /* No PB-frames */ + hdr->tr = s->temp_ref; +} |