1#include "ffmpeg-encoder.h"
  2
  3#include "gba-video.h"
  4
  5#include <libavutil/imgutils.h>
  6
  7static void _ffmpegPostVideoFrame(struct GBAAVStream*, struct GBAVideoRenderer* renderer);
  8static void _ffmpegPostAudioFrame(struct GBAAVStream*, int32_t left, int32_t right);
  9
 10void FFmpegEncoderInit(struct FFmpegEncoder* encoder) {
 11	av_register_all();
 12
 13	encoder->d.postVideoFrame = _ffmpegPostVideoFrame;
 14	encoder->d.postAudioFrame = _ffmpegPostAudioFrame;
 15
 16	FFmpegEncoderSetAudio(encoder, "flac", 0);
 17	FFmpegEncoderSetVideo(encoder, "png", 0);
 18	encoder->currentAudioSample = 0;
 19	encoder->currentAudioFrame = 0;
 20	encoder->currentVideoFrame = 0;
 21}
 22
 23bool FFmpegEncoderSetAudio(struct FFmpegEncoder* encoder, const char* acodec, unsigned abr) {
 24	if (!avcodec_find_encoder_by_name(acodec)) {
 25		return false;
 26	}
 27	encoder->audioCodec = acodec;
 28	encoder->audioBitrate = abr;
 29	return true;
 30}
 31
 32bool FFmpegEncoderSetVideo(struct FFmpegEncoder* encoder, const char* vcodec, unsigned vbr) {
 33	AVCodec* codec = avcodec_find_encoder_by_name(vcodec);
 34	if (!codec) {
 35		return false;
 36	}
 37
 38	size_t i;
 39	encoder->pixFormat = AV_PIX_FMT_NONE;
 40	for (i = 0; codec->pix_fmts[i] != AV_PIX_FMT_NONE; ++i) {
 41		if (codec->pix_fmts[i] == AV_PIX_FMT_RGB24) {
 42			encoder->pixFormat = AV_PIX_FMT_RGB24;
 43			break;
 44		}
 45		if (codec->pix_fmts[i] == AV_PIX_FMT_BGR0) {
 46			encoder->pixFormat = AV_PIX_FMT_BGR0;
 47		}
 48	}
 49	if (encoder->pixFormat == AV_PIX_FMT_NONE) {
 50		return false;
 51	}
 52	encoder->videoCodec = vcodec;
 53	encoder->videoBitrate = vbr;
 54	return true;
 55}
 56
 57bool FFmpegEncoderOpen(struct FFmpegEncoder* encoder, const char* outfile) {
 58	AVCodec* acodec = avcodec_find_encoder_by_name(encoder->audioCodec);
 59	AVCodec* vcodec = avcodec_find_encoder_by_name(encoder->videoCodec);
 60	if (!acodec || !vcodec) {
 61		return false;
 62	}
 63
 64	avformat_alloc_output_context2(&encoder->context, 0, 0, outfile);
 65
 66	encoder->audioStream = avformat_new_stream(encoder->context, acodec);
 67	encoder->audio = encoder->audioStream->codec;
 68	encoder->audio->bit_rate = encoder->audioBitrate;
 69	encoder->audio->sample_rate = 0x8000;
 70	encoder->audio->channels = 2;
 71	encoder->audio->channel_layout = AV_CH_LAYOUT_STEREO;
 72	encoder->audio->sample_fmt = AV_SAMPLE_FMT_S16;
 73	avcodec_open2(encoder->audio, acodec, 0);
 74	encoder->audioFrame = av_frame_alloc();
 75	encoder->audioFrame->nb_samples = encoder->audio->frame_size;
 76	encoder->audioFrame->format = encoder->audio->sample_fmt;
 77	encoder->audioFrame->pts = 0;
 78	encoder->audioBufferSize = av_samples_get_buffer_size(0, encoder->audio->channels, encoder->audio->frame_size, encoder->audio->sample_fmt, 0);
 79	encoder->audioBuffer = av_malloc(encoder->audioBufferSize);
 80	avcodec_fill_audio_frame(encoder->audioFrame, encoder->audio->channels, encoder->audio->sample_fmt, (const uint8_t*) encoder->audioBuffer, encoder->audioBufferSize, 0);
 81
 82	encoder->videoStream = avformat_new_stream(encoder->context, vcodec);
 83	encoder->video = encoder->videoStream->codec;
 84	encoder->video->bit_rate = encoder->videoBitrate;
 85	encoder->video->width = VIDEO_HORIZONTAL_PIXELS;
 86	encoder->video->height = VIDEO_VERTICAL_PIXELS;
 87	encoder->video->time_base = (AVRational) { VIDEO_TOTAL_LENGTH, GBA_ARM7TDMI_FREQUENCY };
 88	encoder->video->pix_fmt = encoder->pixFormat;
 89	encoder->video->gop_size = 15;
 90	encoder->video->max_b_frames = 0;
 91	avcodec_open2(encoder->video, vcodec, 0);
 92	encoder->videoFrame = av_frame_alloc();
 93	encoder->videoFrame->format = encoder->video->pix_fmt;
 94	encoder->videoFrame->width = encoder->video->width;
 95	encoder->videoFrame->height = encoder->video->height;
 96	encoder->videoFrame->pts = 0;
 97	av_image_alloc(encoder->videoFrame->data, encoder->videoFrame->linesize, encoder->video->width, encoder->video->height, encoder->video->pix_fmt, 32);
 98
 99	if (encoder->context->oformat->flags & AVFMT_GLOBALHEADER) {
100		encoder->audio->flags |= CODEC_FLAG_GLOBAL_HEADER;
101		encoder->video->flags |= CODEC_FLAG_GLOBAL_HEADER;
102	}
103
104	avio_open(&encoder->context->pb, outfile, AVIO_FLAG_WRITE);
105	avformat_write_header(encoder->context, 0);
106
107	return true;
108}
109
110void FFmpegEncoderClose(struct FFmpegEncoder* encoder) {
111	av_write_trailer(encoder->context);
112	avio_close(encoder->context->pb);
113
114	av_free(encoder->audioBuffer);
115	av_frame_free(&encoder->audioFrame);
116	avcodec_close(encoder->audio);
117
118	av_frame_free(&encoder->videoFrame);
119	avcodec_close(encoder->video);
120	avformat_free_context(encoder->context);
121}
122
123void _ffmpegPostAudioFrame(struct GBAAVStream* stream, int32_t left, int32_t right) {
124	struct FFmpegEncoder* encoder = (struct FFmpegEncoder*) stream;
125
126	av_frame_make_writable(encoder->audioFrame);
127	encoder->audioBuffer[encoder->currentAudioSample * 2] = left;
128	encoder->audioBuffer[encoder->currentAudioSample * 2 + 1] = right;
129	encoder->audioFrame->pts = av_rescale_q(encoder->currentAudioFrame, encoder->audio->time_base, encoder->audioStream->time_base);
130	++encoder->currentAudioFrame;
131	++encoder->currentAudioSample;
132
133	if ((encoder->currentAudioSample * 4) < encoder->audioBufferSize) {
134		return;
135	}
136	encoder->currentAudioSample = 0;
137
138	AVPacket packet;
139	av_init_packet(&packet);
140	packet.data = 0;
141	packet.size = 0;
142	int gotData;
143	avcodec_encode_audio2(encoder->audio, &packet, encoder->audioFrame, &gotData);
144	if (gotData) {
145		packet.stream_index = encoder->audioStream->index;
146		av_interleaved_write_frame(encoder->context, &packet);
147	}
148	av_free_packet(&packet);
149}
150
151void _ffmpegPostVideoFrame(struct GBAAVStream* stream, struct GBAVideoRenderer* renderer) {
152	struct FFmpegEncoder* encoder = (struct FFmpegEncoder*) stream;
153	uint32_t* pixels;
154	unsigned stride;
155	renderer->getPixels(renderer, &stride, (void**) &pixels);
156
157	AVPacket packet;
158
159	av_init_packet(&packet);
160	packet.data = 0;
161	packet.size = 0;
162	av_frame_make_writable(encoder->videoFrame);
163	encoder->videoFrame->pts = av_rescale_q(encoder->currentVideoFrame, encoder->video->time_base, encoder->videoStream->time_base);
164	++encoder->currentVideoFrame;
165
166	unsigned x, y;
167	if (encoder->videoFrame->format == AV_PIX_FMT_BGR0) {
168		for (y = 0; y < VIDEO_VERTICAL_PIXELS; ++y) {
169			for (x = 0; x < VIDEO_HORIZONTAL_PIXELS; ++x) {
170				uint32_t pixel = pixels[stride * y + x];
171				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 4] = pixel >> 16;
172				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 4 + 1] = pixel >> 8;
173				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 4 + 2] = pixel;
174			}
175		}
176	} else if (encoder->videoFrame->format == AV_PIX_FMT_RGB24) {
177		for (y = 0; y < VIDEO_VERTICAL_PIXELS; ++y) {
178			for (x = 0; x < VIDEO_HORIZONTAL_PIXELS; ++x) {
179				uint32_t pixel = pixels[stride * y + x];
180				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 3] = pixel;
181				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 3 + 1] = pixel >> 8;
182				encoder->videoFrame->data[0][y * encoder->videoFrame->linesize[0] + x * 3 + 2] = pixel >> 16;
183			}
184		}
185	}
186
187	int gotData;
188	avcodec_encode_video2(encoder->video, &packet, encoder->videoFrame, &gotData);
189	if (gotData) {
190		if (encoder->videoStream->codec->coded_frame->key_frame) {
191			packet.flags |= AV_PKT_FLAG_KEY;
192		}
193		packet.stream_index = encoder->videoStream->index;
194		av_interleaved_write_frame(encoder->context, &packet);
195	}
196	av_free_packet(&packet);
197}