joy4/h264enc.go
2013-03-11 11:02:25 +08:00

149 lines
3.0 KiB
Go

package codec
import (
/*
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavutil/avutil.h>
typedef struct {
int w, h;
int pixfmt;
char *preset[2];
char *profile;
int bitrate;
int got;
AVCodec *c;
AVCodecContext *ctx;
AVFrame *f;
AVPacket pkt;
} h264enc_t;
static int h264enc_new(h264enc_t *m) {
m->c = avcodec_find_encoder(CODEC_ID_H264);
m->ctx = avcodec_alloc_context3(m->c);
m->ctx->width = m->w;
m->ctx->height = m->w;
m->ctx->bit_rate = m->bitrate;
m->ctx->pix_fmt = m->pixfmt;
m->ctx->flags |= CODEC_FLAG_GLOBAL_HEADER;
m->f = avcodec_alloc_frame();
return avcodec_open2(m->ctx, m->c, NULL);
}
*/
"C"
"unsafe"
"image"
"errors"
"strings"
//"log"
)
type H264Encoder struct {
m C.h264enc_t
Header []byte
Pixfmt image.YCbCrSubsampleRatio
W, H int
}
func NewH264Encoder(
w, h int,
pixfmt image.YCbCrSubsampleRatio,
opts ...string,
) (m *H264Encoder, err error) {
m = &H264Encoder{}
m.m.w = (C.int)(w)
m.m.h = (C.int)(h)
m.W = w
m.H = h
m.Pixfmt = pixfmt
switch pixfmt {
case image.YCbCrSubsampleRatio444:
m.m.pixfmt = C.PIX_FMT_YUV444P
case image.YCbCrSubsampleRatio422:
m.m.pixfmt = C.PIX_FMT_YUV422P
case image.YCbCrSubsampleRatio420:
m.m.pixfmt = C.PIX_FMT_YUV420P
}
for _, opt := range opts {
a := strings.Split(opt, ",")
switch {
case a[0] == "preset" && len(a) == 3:
m.m.preset[0] = C.CString(a[1])
m.m.preset[1] = C.CString(a[2])
case a[0] == "profile" && len(a) == 2:
m.m.profile = C.CString(a[1])
}
}
r := C.h264enc_new(&m.m)
if int(r) < 0 {
err = errors.New("open encoder failed")
return
}
m.Header = fromCPtr(unsafe.Pointer(m.m.ctx.extradata), (int)(m.m.ctx.extradata_size))
//m.Header = fromCPtr(unsafe.Pointer(m.m.pps), (int)(m.m.ppslen))
return
}
type h264Out struct {
Data []byte
Key bool
}
func (m *H264Encoder) Encode(img *image.YCbCr) (out h264Out, err error) {
var f *C.AVFrame
if img == nil {
f = nil
} else {
if img.SubsampleRatio != m.Pixfmt {
err = errors.New("image pixfmt not match")
return
}
if img.Rect.Dx() != m.W || img.Rect.Dy() != m.H {
err = errors.New("image size not match")
return
}
f = m.m.f
f.data[0] = (*C.uint8_t)(unsafe.Pointer(&img.Y[0]));
f.data[1] = (*C.uint8_t)(unsafe.Pointer(&img.Cb[0]));
f.data[2] = (*C.uint8_t)(unsafe.Pointer(&img.Cr[0]));
f.linesize[0] = (C.int)(img.YStride);
f.linesize[1] = (C.int)(img.CStride);
f.linesize[2] = (C.int)(img.CStride);
}
C.av_init_packet(&m.m.pkt)
r := C.avcodec_encode_video2(m.m.ctx, &m.m.pkt, f, &m.m.got)
defer C.av_free_packet(&m.m.pkt)
if int(r) < 0 {
err = errors.New("encode failed")
return
}
if m.m.got == 0 {
err = errors.New("no picture")
return
}
if (m.m.pkt.size == 0) {
err = errors.New("packet size == 0")
return
}
out.Data = make([]byte, m.m.pkt.size)
C.memcpy(
unsafe.Pointer(&out.Data[0]),
unsafe.Pointer(m.m.pkt.data),
(C.size_t)(m.m.pkt.size),
)
out.Key = (m.m.pkt.flags & C.AV_PKT_FLAG_KEY) != 0
return
}