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codecCtx_go112.go
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codecCtx_go112.go
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// +build go1.12
package gmf
/*
#cgo pkg-config: libavcodec libavutil
#include <string.h>
#include <stdint.h>
#include "libavcodec/avcodec.h"
#include "libavutil/channel_layout.h"
#include "libavutil/samplefmt.h"
#include "libavutil/opt.h"
#include "libavutil/mem.h"
#include "libavutil/bprint.h"
#define HAVE_THREADS 1
static int32_t gmf_select_sample_fmt(AVCodec *codec)
{
if (codec && codec->sample_fmts) {
return codec->sample_fmts[0];
}
return -1;
}
static int check_sample_fmt(AVCodec *codec, enum AVSampleFormat sample_fmt) {
const enum AVSampleFormat *p = codec->sample_fmts;
while (*p != AV_SAMPLE_FMT_NONE) {
if (*p == sample_fmt)
return 1;
p++;
}
return 0;
}
static int select_sample_rate(AVCodec *codec) {
const int *p;
int best_samplerate = 0;
if (!codec->supported_samplerates)
return 44100;
p = codec->supported_samplerates;
while (*p) {
best_samplerate = FFMAX(*p, best_samplerate);
p++;
}
return best_samplerate;
}
static int gmf_check_sample_rate(AVCodec *codec, int input_sample_rate) {
const int *p;
if ((p = codec->supported_samplerates) == NULL) {
return 1;
}
while (*p) {
if (*p == input_sample_rate) {
return 1;
}
p++;
}
return 0;
}
static int select_channel_layout(AVCodec *codec) {
const uint64_t *p;
uint64_t best_ch_layout = 0;
int best_nb_channels = 0;
if (!codec->channel_layouts)
return AV_CH_LAYOUT_STEREO;
p = codec->channel_layouts;
while (*p) {
int nb_channels = av_get_channel_layout_nb_channels(*p);
if (nb_channels > best_nb_channels) {
best_ch_layout = *p;
best_nb_channels = nb_channels;
}
p++;
}
return best_ch_layout;
}
static void call_av_freep(AVCodecContext *out){
return av_freep(&out);
}
static char * gmf_get_channel_layout_name(int channels, int layout) {
AVBPrint pbuf;
av_bprint_init(&pbuf, 0, 1);
av_bprint_channel_layout(&pbuf, channels, layout);
char *result = av_mallocz(pbuf.len);
memcpy(result, pbuf.str, pbuf.len);
av_bprint_clear(&pbuf);
return result;
}
static void priv_data_opt_set(AVCodecContext *cc, char *name, char *value)
{
av_opt_set(cc->priv_data, name, value, 0);
}
*/
import "C"
import (
"errors"
"fmt"
"syscall"
"unsafe"
)
const (
AVCOL_RANGE_UNSPECIFIED = iota
AVCOL_RANGE_MPEG ///< the normal 219*2^(n-8) "MPEG" YUV ranges
AVCOL_RANGE_JPEG ///< the normal 2^n-1 "JPEG" YUV ranges
AVCOL_RANGE_NB ///< Not part of ABI
)
var (
AV_CODEC_ID_MPEG1VIDEO int = C.AV_CODEC_ID_MPEG1VIDEO
AV_CODEC_ID_MPEG2VIDEO int = C.AV_CODEC_ID_MPEG2VIDEO
AV_CODEC_ID_H264 int = C.AV_CODEC_ID_H264
AV_CODEC_ID_MPEG4 int = C.AV_CODEC_ID_MPEG4
AV_CODEC_ID_JPEG2000 int = C.AV_CODEC_ID_JPEG2000
AV_CODEC_ID_MJPEG int = C.AV_CODEC_ID_MJPEG
AV_CODEC_ID_MSMPEG4V1 int = C.AV_CODEC_ID_MSMPEG4V1
AV_CODEC_ID_MSMPEG4V2 int = C.AV_CODEC_ID_MSMPEG4V2
AV_CODEC_ID_MSMPEG4V3 int = C.AV_CODEC_ID_MSMPEG4V3
AV_CODEC_ID_WMV1 int = C.AV_CODEC_ID_WMV1
AV_CODEC_ID_WMV2 int = C.AV_CODEC_ID_WMV2
AV_CODEC_ID_FLV1 int = C.AV_CODEC_ID_FLV1
AV_CODEC_ID_PNG int = C.AV_CODEC_ID_PNG
AV_CODEC_ID_TIFF int = C.AV_CODEC_ID_TIFF
AV_CODEC_ID_GIF int = C.AV_CODEC_ID_GIF
AV_CODEC_ID_RAWVIDEO int = C.AV_CODEC_ID_RAWVIDEO
CODEC_FLAG_GLOBAL_HEADER int = C.AV_CODEC_FLAG_GLOBAL_HEADER
AV_CODEC_FLAG_QSCALE int32 = C.AV_CODEC_FLAG_QSCALE
FF_MB_DECISION_SIMPLE int = C.FF_MB_DECISION_SIMPLE
FF_MB_DECISION_BITS int = C.FF_MB_DECISION_BITS
FF_MB_DECISION_RD int = C.FF_MB_DECISION_RD
FF_QP2LAMBDA int = C.FF_QP2LAMBDA
AV_SAMPLE_FMT_U8 int32 = C.AV_SAMPLE_FMT_U8
AV_SAMPLE_FMT_S16 int32 = C.AV_SAMPLE_FMT_S16
AV_SAMPLE_FMT_S32 int32 = C.AV_SAMPLE_FMT_S32
AV_SAMPLE_FMT_FLT int32 = C.AV_SAMPLE_FMT_FLT
AV_SAMPLE_FMT_DBL int32 = C.AV_SAMPLE_FMT_DBL
AV_SAMPLE_FMT_U8P int32 = C.AV_SAMPLE_FMT_U8P
AV_SAMPLE_FMT_S16P int32 = C.AV_SAMPLE_FMT_S16P
AV_SAMPLE_FMT_S32P int32 = C.AV_SAMPLE_FMT_S32P
AV_SAMPLE_FMT_FLTP int32 = C.AV_SAMPLE_FMT_FLTP
AV_SAMPLE_FMT_DBLP int32 = C.AV_SAMPLE_FMT_DBLP
color_range_names map[uint32]string = map[uint32]string{
AVCOL_RANGE_UNSPECIFIED: "unknown",
AVCOL_RANGE_MPEG: "tv",
AVCOL_RANGE_JPEG: "pc",
}
)
type avBprint C.struct_AVBprint
type CodecCtx struct {
codec *Codec
avCodecCtx *C.struct_AVCodecContext
CgoMemoryManage
}
func NewCodecCtx(codec *Codec, options ...[]*Option) *CodecCtx {
result := &CodecCtx{codec: codec}
codecctx := C.avcodec_alloc_context3(codec.avCodec)
if codecctx == nil {
return nil
}
result.avCodecCtx = codecctx
// we're really expecting only one options-array —
// variadic arg is used for backward compatibility
if len(options) == 1 {
for _, option := range options[0] {
option.Set(result.avCodecCtx)
}
}
result.avCodecCtx.codec_id = codec.avCodec.id
return result
}
func (cc *CodecCtx) SetOptions(options []Option) {
for _, option := range options {
option.Set(cc.avCodecCtx)
}
}
func (cc *CodecCtx) CopyExtra(ist *Stream) *CodecCtx {
codec := cc.avCodecCtx
icodec := ist.CodecCtx().avCodecCtx
codec.bits_per_raw_sample = icodec.bits_per_raw_sample
codec.chroma_sample_location = icodec.chroma_sample_location
codec.codec_id = icodec.codec_id
codec.codec_type = icodec.codec_type
// codec.codec_tag = icodec.codec_tag
codec.rc_max_rate = icodec.rc_max_rate
codec.rc_buffer_size = icodec.rc_buffer_size
codec.field_order = icodec.field_order
codec.extradata = (*C.uint8_t)(C.av_mallocz((C.size_t)((C.uint64_t)(icodec.extradata_size) + C.AV_INPUT_BUFFER_PADDING_SIZE)))
C.memcpy(unsafe.Pointer(codec.extradata), unsafe.Pointer(icodec.extradata), (C.size_t)(icodec.extradata_size))
codec.extradata_size = icodec.extradata_size
codec.bits_per_coded_sample = icodec.bits_per_coded_sample
codec.has_b_frames = icodec.has_b_frames
return cc
}
func (cc *CodecCtx) Open(dict *Dict) error {
if cc.IsOpen() {
return nil
}
var avDict *C.struct_AVDictionary
if dict != nil {
avDict = dict.avDict
}
if cc.Codec().IsDecoder() {
cc.avCodecCtx.thread_count = 4
cc.avCodecCtx.thread_type = 3
}
if averr := C.avcodec_open2(cc.avCodecCtx, cc.codec.avCodec, &avDict); averr < 0 {
return errors.New(fmt.Sprintf("Error opening codec '%s:%s', averror: %s", cc.codec.Name(), cc.codec.LongName(), AvError(int(averr))))
}
return nil
}
// codec context is freed by avformat_free_context()
func (cc *CodecCtx) Free() {
if cc.avCodecCtx != nil {
C.avcodec_free_context(&cc.avCodecCtx)
}
}
func (cc *CodecCtx) CloseAndRelease() {
panic("(CodecCtx)CloseAndRelease() is deprecated")
}
func (cc *CodecCtx) Close() {
C.avcodec_close(cc.avCodecCtx)
}
// @todo
func (cc *CodecCtx) SetOpt() {
// mock
C.av_opt_set_int(unsafe.Pointer(cc.avCodecCtx), C.CString("refcounted_frames"), 1, 0)
}
func (cc *CodecCtx) SetPrivDataOpt(name, value string) {
C.priv_data_opt_set(cc.avCodecCtx, C.CString(name), C.CString(value))
}
func (cc *CodecCtx) Codec() *Codec {
return &Codec{avCodec: cc.avCodecCtx.codec}
}
func (cc *CodecCtx) Id() int {
return int(cc.avCodecCtx.codec_id)
}
func (cc *CodecCtx) Type() int32 {
return int32(cc.avCodecCtx.codec_type)
}
func (cc *CodecCtx) Width() int {
return int(cc.avCodecCtx.width)
}
func (cc *CodecCtx) Height() int {
return int(cc.avCodecCtx.height)
}
func (cc *CodecCtx) PixFmt() int32 {
return int32(cc.avCodecCtx.pix_fmt)
}
func (cc *CodecCtx) FrameSize() int {
return int(cc.avCodecCtx.frame_size)
}
func (cc *CodecCtx) SampleFmt() int32 {
return cc.avCodecCtx.sample_fmt
}
func (cc *CodecCtx) SampleRate() int {
return int(cc.avCodecCtx.sample_rate)
}
func (cc *CodecCtx) Profile() int {
return int(cc.avCodecCtx.profile)
}
func (cc *CodecCtx) IsOpen() bool {
return (int(C.avcodec_is_open(cc.avCodecCtx)) > 0)
}
func (cc *CodecCtx) SetProfile(profile int) *CodecCtx {
cc.avCodecCtx.profile = C.int(profile)
return cc
}
func (cc *CodecCtx) SetCodecPreset(preset string) *CodecCtx {
cc.SetPrivDataOpt("preset", preset)
return cc
}
func (cc *CodecCtx) SetCodecTune(tune string) *CodecCtx {
cc.SetPrivDataOpt("tune", tune)
return cc
}
func (cc *CodecCtx) TimeBase() AVRational {
return AVRational(cc.avCodecCtx.time_base)
}
func (cc *CodecCtx) ChannelLayout() int {
return int(cc.avCodecCtx.channel_layout)
}
func (cc *CodecCtx) SetChannelLayout(channelLayout int) {
cc.avCodecCtx.channel_layout = C.uint64_t(channelLayout)
}
func (cc *CodecCtx) BitRate() int {
return int(cc.avCodecCtx.bit_rate)
}
func (cc *CodecCtx) Channels() int {
return int(cc.avCodecCtx.channels)
}
func (cc *CodecCtx) SetBitRate(val int) *CodecCtx {
cc.avCodecCtx.bit_rate = C.int64_t(val)
return cc
}
func (cc *CodecCtx) SetWidth(val int) *CodecCtx {
cc.avCodecCtx.width = C.int(val)
return cc
}
func (cc *CodecCtx) SetHeight(val int) *CodecCtx {
cc.avCodecCtx.height = C.int(val)
return cc
}
func (cc *CodecCtx) SetDimension(w, h int) *CodecCtx {
cc.avCodecCtx.width = C.int(w)
cc.avCodecCtx.height = C.int(h)
return cc
}
func (cc *CodecCtx) SetTimeBase(val AVR) *CodecCtx {
cc.avCodecCtx.time_base.num = C.int(val.Num)
cc.avCodecCtx.time_base.den = C.int(val.Den)
return cc
}
func (cc *CodecCtx) SetGopSize(val int) *CodecCtx {
cc.avCodecCtx.gop_size = C.int(val)
return cc
}
func (cc *CodecCtx) GetGopSize() int {
return int(cc.avCodecCtx.gop_size)
}
func (cc *CodecCtx) SetMaxBFrames(val int) *CodecCtx {
cc.avCodecCtx.max_b_frames = C.int(val)
return cc
}
func (cc *CodecCtx) SetPixFmt(val int32) *CodecCtx {
cc.avCodecCtx.pix_fmt = val
return cc
}
func (cc *CodecCtx) SetFlag(flag int) *CodecCtx {
cc.avCodecCtx.flags |= C.int(flag)
return cc
}
func (cc *CodecCtx) SetMbDecision(val int) *CodecCtx {
cc.avCodecCtx.mb_decision = C.int(val)
return cc
}
func (cc *CodecCtx) SetSampleFmt(val int32) *CodecCtx {
if int(C.check_sample_fmt(cc.codec.avCodec, val)) == 0 {
panic(fmt.Sprintf("encoder doesn't support sample format %s", GetSampleFmtName(val)))
}
cc.avCodecCtx.sample_fmt = val
return cc
}
func (cc *CodecCtx) SetSampleRate(val int) *CodecCtx {
cc.avCodecCtx.sample_rate = C.int(val)
return cc
}
var (
FF_COMPLIANCE_VERY_STRICT int = C.FF_COMPLIANCE_VERY_STRICT
FF_COMPLIANCE_STRICT int = C.FF_COMPLIANCE_STRICT
FF_COMPLIANCE_NORMAL int = C.FF_COMPLIANCE_NORMAL
FF_COMPLIANCE_UNOFFICIAL int = C.FF_COMPLIANCE_UNOFFICIAL
FF_COMPLIANCE_EXPERIMENTAL int = C.FF_COMPLIANCE_EXPERIMENTAL
)
func (cc *CodecCtx) SetStrictCompliance(val int) *CodecCtx {
cc.avCodecCtx.strict_std_compliance = C.int(val)
return cc
}
func (cc *CodecCtx) SetHasBframes(val int) *CodecCtx {
cc.avCodecCtx.has_b_frames = C.int(val)
return cc
}
func (cc *CodecCtx) SetChannels(val int) *CodecCtx {
cc.avCodecCtx.channels = C.int(val)
return cc
}
func (cc *CodecCtx) SetFrameRate(r AVR) *CodecCtx {
cc.avCodecCtx.framerate.num = C.int(r.Num)
cc.avCodecCtx.framerate.den = C.int(r.Den)
return cc
}
func (cc *CodecCtx) SetBitsPerRawSample(val int) *CodecCtx {
cc.avCodecCtx.bits_per_raw_sample = C.int(val)
return cc
}
func (cc *CodecCtx) SelectSampleRate() int {
return int(C.select_sample_rate(cc.codec.avCodec))
}
func (cc *CodecCtx) SelectChannelLayout() int {
return int(C.select_channel_layout(cc.codec.avCodec))
}
func (cc *CodecCtx) FlushBuffers() {
C.avcodec_flush_buffers(cc.avCodecCtx)
}
func (cc *CodecCtx) Dump() {
fmt.Println(cc.avCodecCtx)
}
func (cc *CodecCtx) GetFrameRate() AVRational {
return AVRational(cc.avCodecCtx.framerate)
}
func (cc *CodecCtx) GetProfile() int {
return int(cc.avCodecCtx.profile)
}
func (cc *CodecCtx) GetProfileName() string {
return C.GoString(C.avcodec_profile_name(cc.avCodecCtx.codec_id, cc.avCodecCtx.profile))
}
func (cc *CodecCtx) GetMediaType() string {
return C.GoString(C.av_get_media_type_string(cc.avCodecCtx.codec_type))
}
func (cc *CodecCtx) GetCodecTag() uint32 {
return uint32(cc.avCodecCtx.codec_tag)
}
func (cc *CodecCtx) GetCodecTagName() string {
var (
ct uint32 = uint32(cc.avCodecCtx.codec_tag)
result string
)
for i := 0; i < 4; i++ {
c := ct & 0xff
result += fmt.Sprintf("%c", c)
ct >>= 8
}
return fmt.Sprintf("%v", result)
}
func (cc *CodecCtx) GetCodedWith() int {
return int(cc.avCodecCtx.coded_width)
}
func (cc *CodecCtx) GetCodedHeight() int {
return int(cc.avCodecCtx.coded_height)
}
func (cc *CodecCtx) GetBFrames() int {
return int(cc.avCodecCtx.has_b_frames)
}
func (cc *CodecCtx) GetPixFmtName() string {
// return C.GoString(C.av_get_pix_fmt_name(cc.avCodecCtx.pix_fmt))
return "unknown"
}
func (cc *CodecCtx) GetColorRangeName() string {
return color_range_names[cc.avCodecCtx.color_range]
}
func (cc *CodecCtx) GetRefs() int {
return int(cc.avCodecCtx.refs)
}
func (cc *CodecCtx) GetSampleFmtName() string {
return C.GoString(C.av_get_sample_fmt_name(cc.avCodecCtx.sample_fmt))
}
func (cc *CodecCtx) GetChannelLayoutName() string {
str := C.GoString(C.gmf_get_channel_layout_name(C.int(cc.Channels()), C.int(cc.ChannelLayout())))
return str
}
func (cc *CodecCtx) GetDefaultChannelLayout(ac int) int {
return int(C.av_get_default_channel_layout(C.int(ac)))
}
func (cc *CodecCtx) GetBitsPerSample() int {
return int(C.av_get_bits_per_sample(cc.codec.avCodec.id))
}
func (cc *CodecCtx) GetVideoSize() string {
return fmt.Sprintf("%dx%d", cc.Width(), cc.Height())
}
func (cc *CodecCtx) GetAspectRation() AVRational {
return AVRational(cc.avCodecCtx.sample_aspect_ratio)
}
func (cc *CodecCtx) Decode(pkt *Packet) ([]*Frame, error) {
var (
ret int
result []*Frame = make([]*Frame, 0)
)
if pkt == nil {
ret = int(C.avcodec_send_packet(cc.avCodecCtx, nil))
} else {
ret = int(C.avcodec_send_packet(cc.avCodecCtx, &pkt.avPacket))
}
if ret < 0 {
return nil, AvError(ret)
}
for {
frame := NewFrame()
ret = int(C.avcodec_receive_frame(cc.avCodecCtx, frame.avFrame))
if AvErrno(ret) == syscall.EAGAIN || ret == AVERROR_EOF {
frame.Free()
break
} else if ret < 0 {
frame.Free()
return nil, AvError(ret)
}
result = append(result, frame)
}
return result, nil
}
func (cc *CodecCtx) Encode(frames []*Frame, drain int) ([]*Packet, error) {
var (
ret int
result []*Packet = make([]*Packet, 0)
)
if len(frames) == 0 && drain >= 0 {
frames = append(frames, nil)
}
for _, frame := range frames {
if frame == nil {
ret = int(C.avcodec_send_frame(cc.avCodecCtx, nil))
} else {
ret = int(C.avcodec_send_frame(cc.avCodecCtx, frame.avFrame))
}
if ret < 0 {
return nil, AvError(ret)
}
for {
pkt := NewPacket()
ret = int(C.avcodec_receive_packet(cc.avCodecCtx, &pkt.avPacket))
if ret < 0 {
pkt.Free()
break
}
result = append(result, pkt)
}
if frame != nil {
frame.Free()
}
}
return result, nil
}
func (cc *CodecCtx) Decode2(pkt *Packet) (*Frame, int) {
var (
ret int
)
if pkt == nil {
ret = int(C.avcodec_send_packet(cc.avCodecCtx, nil))
} else {
ret = int(C.avcodec_send_packet(cc.avCodecCtx, &pkt.avPacket))
}
if ret < 0 {
return nil, ret
}
frame := NewFrame()
if ret = int(C.avcodec_receive_frame(cc.avCodecCtx, frame.avFrame)); ret < 0 {
return nil, ret
}
return frame, 0
}
func (cc *CodecCtx) SelectSampleFmt() int32 {
return int32(C.gmf_select_sample_fmt(cc.codec.avCodec))
}
func (cc *CodecCtx) SupportedSampleRate(val int) bool {
return int(C.gmf_check_sample_rate(cc.codec.avCodec, C.int(val))) == 1
}
func (cc *CodecCtx) SetGlobalQuality(val int) {
cc.avCodecCtx.global_quality = C.int(val)
}
func (cc *CodecCtx) SetPktTimeBase(val AVR) {
cc.avCodecCtx.pkt_timebase.num = C.int(val.Num)
cc.avCodecCtx.pkt_timebase.den = C.int(val.Den)
}
func (cc *CodecCtx) SetThreadCount(val int) {
cc.avCodecCtx.thread_count = C.int(val)
}