scrcpy/app/src/recorder.c
2021-04-10 18:48:52 +02:00

378 lines
11 KiB
C

#include "recorder.h"
#include <assert.h>
#include <libavutil/time.h>
#include "util/log.h"
static const AVRational SCRCPY_TIME_BASE = {1, 1000000}; // timestamps in us
static const AVOutputFormat *
find_muxer(const char *name) {
#ifdef SCRCPY_LAVF_HAS_NEW_MUXER_ITERATOR_API
void *opaque = NULL;
#endif
const AVOutputFormat *oformat = NULL;
do {
#ifdef SCRCPY_LAVF_HAS_NEW_MUXER_ITERATOR_API
oformat = av_muxer_iterate(&opaque);
#else
oformat = av_oformat_next(oformat);
#endif
// until null or with name "mp4"
} while (oformat && strcmp(oformat->name, name));
return oformat;
}
static struct record_packet *
record_packet_new(const AVPacket *packet) {
struct record_packet *rec = malloc(sizeof(*rec));
if (!rec) {
return NULL;
}
// av_packet_ref() does not initialize all fields in old FFmpeg versions
// See <https://github.com/Genymobile/scrcpy/issues/707>
av_init_packet(&rec->packet);
if (av_packet_ref(&rec->packet, packet)) {
free(rec);
return NULL;
}
return rec;
}
static void
record_packet_delete(struct record_packet *rec) {
av_packet_unref(&rec->packet);
free(rec);
}
static void
recorder_queue_clear(struct recorder_queue *queue) {
while (!queue_is_empty(queue)) {
struct record_packet *rec;
queue_take(queue, next, &rec);
record_packet_delete(rec);
}
}
bool
recorder_init(struct recorder *recorder,
const char *filename,
enum sc_record_format format,
struct size declared_frame_size) {
recorder->filename = strdup(filename);
if (!recorder->filename) {
LOGE("Could not strdup filename");
return false;
}
bool ok = sc_mutex_init(&recorder->mutex);
if (!ok) {
LOGC("Could not create mutex");
free(recorder->filename);
return false;
}
ok = sc_cond_init(&recorder->queue_cond);
if (!ok) {
LOGC("Could not create cond");
sc_mutex_destroy(&recorder->mutex);
free(recorder->filename);
return false;
}
queue_init(&recorder->queue);
recorder->stopped = false;
recorder->failed = false;
recorder->format = format;
recorder->declared_frame_size = declared_frame_size;
recorder->header_written = false;
recorder->previous = NULL;
return true;
}
void
recorder_destroy(struct recorder *recorder) {
sc_cond_destroy(&recorder->queue_cond);
sc_mutex_destroy(&recorder->mutex);
free(recorder->filename);
}
static const char *
recorder_get_format_name(enum sc_record_format format) {
switch (format) {
case SC_RECORD_FORMAT_MP4: return "mp4";
case SC_RECORD_FORMAT_MKV: return "matroska";
default: return NULL;
}
}
bool
recorder_open(struct recorder *recorder, const AVCodec *input_codec) {
const char *format_name = recorder_get_format_name(recorder->format);
assert(format_name);
const AVOutputFormat *format = find_muxer(format_name);
if (!format) {
LOGE("Could not find muxer");
return false;
}
recorder->ctx = avformat_alloc_context();
if (!recorder->ctx) {
LOGE("Could not allocate output context");
return false;
}
// contrary to the deprecated API (av_oformat_next()), av_muxer_iterate()
// returns (on purpose) a pointer-to-const, but AVFormatContext.oformat
// still expects a pointer-to-non-const (it has not be updated accordingly)
// <https://github.com/FFmpeg/FFmpeg/commit/0694d8702421e7aff1340038559c438b61bb30dd>
recorder->ctx->oformat = (AVOutputFormat *) format;
av_dict_set(&recorder->ctx->metadata, "comment",
"Recorded by scrcpy " SCRCPY_VERSION, 0);
AVStream *ostream = avformat_new_stream(recorder->ctx, input_codec);
if (!ostream) {
avformat_free_context(recorder->ctx);
return false;
}
#ifdef SCRCPY_LAVF_HAS_NEW_CODEC_PARAMS_API
ostream->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
ostream->codecpar->codec_id = input_codec->id;
ostream->codecpar->format = AV_PIX_FMT_YUV420P;
ostream->codecpar->width = recorder->declared_frame_size.width;
ostream->codecpar->height = recorder->declared_frame_size.height;
#else
ostream->codec->codec_type = AVMEDIA_TYPE_VIDEO;
ostream->codec->codec_id = input_codec->id;
ostream->codec->pix_fmt = AV_PIX_FMT_YUV420P;
ostream->codec->width = recorder->declared_frame_size.width;
ostream->codec->height = recorder->declared_frame_size.height;
#endif
int ret = avio_open(&recorder->ctx->pb, recorder->filename,
AVIO_FLAG_WRITE);
if (ret < 0) {
LOGE("Failed to open output file: %s", recorder->filename);
// ostream will be cleaned up during context cleaning
avformat_free_context(recorder->ctx);
return false;
}
LOGI("Recording started to %s file: %s", format_name, recorder->filename);
return true;
}
void
recorder_close(struct recorder *recorder) {
if (recorder->header_written) {
int ret = av_write_trailer(recorder->ctx);
if (ret < 0) {
LOGE("Failed to write trailer to %s", recorder->filename);
recorder->failed = true;
}
} else {
// the recorded file is empty
recorder->failed = true;
}
avio_close(recorder->ctx->pb);
avformat_free_context(recorder->ctx);
if (recorder->failed) {
LOGE("Recording failed to %s", recorder->filename);
} else {
const char *format_name = recorder_get_format_name(recorder->format);
LOGI("Recording complete to %s file: %s", format_name, recorder->filename);
}
}
static bool
recorder_write_header(struct recorder *recorder, const AVPacket *packet) {
AVStream *ostream = recorder->ctx->streams[0];
uint8_t *extradata = av_malloc(packet->size * sizeof(uint8_t));
if (!extradata) {
LOGC("Could not allocate extradata");
return false;
}
// copy the first packet to the extra data
memcpy(extradata, packet->data, packet->size);
#ifdef SCRCPY_LAVF_HAS_NEW_CODEC_PARAMS_API
ostream->codecpar->extradata = extradata;
ostream->codecpar->extradata_size = packet->size;
#else
ostream->codec->extradata = extradata;
ostream->codec->extradata_size = packet->size;
#endif
int ret = avformat_write_header(recorder->ctx, NULL);
if (ret < 0) {
LOGE("Failed to write header to %s", recorder->filename);
return false;
}
return true;
}
static void
recorder_rescale_packet(struct recorder *recorder, AVPacket *packet) {
AVStream *ostream = recorder->ctx->streams[0];
av_packet_rescale_ts(packet, SCRCPY_TIME_BASE, ostream->time_base);
}
static bool
recorder_write(struct recorder *recorder, AVPacket *packet) {
if (!recorder->header_written) {
if (packet->pts != AV_NOPTS_VALUE) {
LOGE("The first packet is not a config packet");
return false;
}
bool ok = recorder_write_header(recorder, packet);
if (!ok) {
return false;
}
recorder->header_written = true;
return true;
}
if (packet->pts == AV_NOPTS_VALUE) {
// ignore config packets
return true;
}
recorder_rescale_packet(recorder, packet);
return av_write_frame(recorder->ctx, packet) >= 0;
}
static int
run_recorder(void *data) {
struct recorder *recorder = data;
for (;;) {
sc_mutex_lock(&recorder->mutex);
while (!recorder->stopped && queue_is_empty(&recorder->queue)) {
sc_cond_wait(&recorder->queue_cond, &recorder->mutex);
}
// if stopped is set, continue to process the remaining events (to
// finish the recording) before actually stopping
if (recorder->stopped && queue_is_empty(&recorder->queue)) {
sc_mutex_unlock(&recorder->mutex);
struct record_packet *last = recorder->previous;
if (last) {
// assign an arbitrary duration to the last packet
last->packet.duration = 100000;
bool ok = recorder_write(recorder, &last->packet);
if (!ok) {
// failing to write the last frame is not very serious, no
// future frame may depend on it, so the resulting file
// will still be valid
LOGW("Could not record last packet");
}
record_packet_delete(last);
}
break;
}
struct record_packet *rec;
queue_take(&recorder->queue, next, &rec);
sc_mutex_unlock(&recorder->mutex);
// recorder->previous is only written from this thread, no need to lock
struct record_packet *previous = recorder->previous;
recorder->previous = rec;
if (!previous) {
// we just received the first packet
continue;
}
// config packets have no PTS, we must ignore them
if (rec->packet.pts != AV_NOPTS_VALUE
&& previous->packet.pts != AV_NOPTS_VALUE) {
// we now know the duration of the previous packet
previous->packet.duration = rec->packet.pts - previous->packet.pts;
}
bool ok = recorder_write(recorder, &previous->packet);
record_packet_delete(previous);
if (!ok) {
LOGE("Could not record packet");
sc_mutex_lock(&recorder->mutex);
recorder->failed = true;
// discard pending packets
recorder_queue_clear(&recorder->queue);
sc_mutex_unlock(&recorder->mutex);
break;
}
}
LOGD("Recorder thread ended");
return 0;
}
bool
recorder_start(struct recorder *recorder) {
LOGD("Starting recorder thread");
bool ok = sc_thread_create(&recorder->thread, run_recorder, "recorder",
recorder);
if (!ok) {
LOGC("Could not start recorder thread");
return false;
}
return true;
}
void
recorder_stop(struct recorder *recorder) {
sc_mutex_lock(&recorder->mutex);
recorder->stopped = true;
sc_cond_signal(&recorder->queue_cond);
sc_mutex_unlock(&recorder->mutex);
}
void
recorder_join(struct recorder *recorder) {
sc_thread_join(&recorder->thread, NULL);
}
bool
recorder_push(struct recorder *recorder, const AVPacket *packet) {
sc_mutex_lock(&recorder->mutex);
assert(!recorder->stopped);
if (recorder->failed) {
// reject any new packet (this will stop the stream)
sc_mutex_unlock(&recorder->mutex);
return false;
}
struct record_packet *rec = record_packet_new(packet);
if (!rec) {
LOGC("Could not allocate record packet");
sc_mutex_unlock(&recorder->mutex);
return false;
}
queue_push(&recorder->queue, next, rec);
sc_cond_signal(&recorder->queue_cond);
sc_mutex_unlock(&recorder->mutex);
return true;
}