1/*
2 * Video Acceleration API (video transcoding) transcode sample
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
20 * THE SOFTWARE.
21 */
22
23/**
24 * @file
25 * Intel VAAPI-accelerated transcoding example.
26 *
27 * @example vaapi_transcode.c
28 * This example shows how to do VAAPI-accelerated transcoding.
29 * Usage: vaapi_transcode input_stream codec output_stream
30 * e.g: - vaapi_transcode input.mp4 h264_vaapi output_h264.mp4
31 *      - vaapi_transcode input.mp4 vp9_vaapi output_vp9.ivf
32 */
33
34#include <stdio.h>
35#include <errno.h>
36
37#include <libavutil/hwcontext.h>
38#include <libavcodec/avcodec.h>
39#include <libavformat/avformat.h>
40
41static AVFormatContext *ifmt_ctx = NULL, *ofmt_ctx = NULL;
42static AVBufferRef *hw_device_ctx = NULL;
43static AVCodecContext *decoder_ctx = NULL, *encoder_ctx = NULL;
44static int video_stream = -1;
45static AVStream *ost;
46static int initialized = 0;
47
48static enum AVPixelFormat get_vaapi_format(AVCodecContext *ctx,
49                                           const enum AVPixelFormat *pix_fmts)
50{
51    const enum AVPixelFormat *p;
52
53    for (p = pix_fmts; *p != AV_PIX_FMT_NONE; p++) {
54        if (*p == AV_PIX_FMT_VAAPI)
55            return *p;
56    }
57
58    fprintf(stderr, "Unable to decode this file using VA-API.\n");
59    return AV_PIX_FMT_NONE;
60}
61
62static int open_input_file(const char *filename)
63{
64    int ret;
65    const AVCodec *decoder = NULL;
66    AVStream *video = NULL;
67
68    if ((ret = avformat_open_input(&ifmt_ctx, filename, NULL, NULL)) < 0) {
69        fprintf(stderr, "Cannot open input file '%s', Error code: %s\n",
70                filename, av_err2str(ret));
71        return ret;
72    }
73
74    if ((ret = avformat_find_stream_info(ifmt_ctx, NULL)) < 0) {
75        fprintf(stderr, "Cannot find input stream information. Error code: %s\n",
76                av_err2str(ret));
77        return ret;
78    }
79
80    ret = av_find_best_stream(ifmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);
81    if (ret < 0) {
82        fprintf(stderr, "Cannot find a video stream in the input file. "
83                "Error code: %s\n", av_err2str(ret));
84        return ret;
85    }
86    video_stream = ret;
87
88    if (!(decoder_ctx = avcodec_alloc_context3(decoder)))
89        return AVERROR(ENOMEM);
90
91    video = ifmt_ctx->streams[video_stream];
92    if ((ret = avcodec_parameters_to_context(decoder_ctx, video->codecpar)) < 0) {
93        fprintf(stderr, "avcodec_parameters_to_context error. Error code: %s\n",
94                av_err2str(ret));
95        return ret;
96    }
97
98    decoder_ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);
99    if (!decoder_ctx->hw_device_ctx) {
100        fprintf(stderr, "A hardware device reference create failed.\n");
101        return AVERROR(ENOMEM);
102    }
103    decoder_ctx->get_format    = get_vaapi_format;
104
105    if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0)
106        fprintf(stderr, "Failed to open codec for decoding. Error code: %s\n",
107                av_err2str(ret));
108
109    return ret;
110}
111
112static int encode_write(AVPacket *enc_pkt, AVFrame *frame)
113{
114    int ret = 0;
115
116    av_packet_unref(enc_pkt);
117
118    if ((ret = avcodec_send_frame(encoder_ctx, frame)) < 0) {
119        fprintf(stderr, "Error during encoding. Error code: %s\n", av_err2str(ret));
120        goto end;
121    }
122    while (1) {
123        ret = avcodec_receive_packet(encoder_ctx, enc_pkt);
124        if (ret)
125            break;
126
127        enc_pkt->stream_index = 0;
128        av_packet_rescale_ts(enc_pkt, ifmt_ctx->streams[video_stream]->time_base,
129                             ofmt_ctx->streams[0]->time_base);
130        ret = av_interleaved_write_frame(ofmt_ctx, enc_pkt);
131        if (ret < 0) {
132            fprintf(stderr, "Error during writing data to output file. "
133                    "Error code: %s\n", av_err2str(ret));
134            return -1;
135        }
136    }
137
138end:
139    if (ret == AVERROR_EOF)
140        return 0;
141    ret = ((ret == AVERROR(EAGAIN)) ? 0:-1);
142    return ret;
143}
144
145static int dec_enc(AVPacket *pkt, const AVCodec *enc_codec)
146{
147    AVFrame *frame;
148    int ret = 0;
149
150    ret = avcodec_send_packet(decoder_ctx, pkt);
151    if (ret < 0) {
152        fprintf(stderr, "Error during decoding. Error code: %s\n", av_err2str(ret));
153        return ret;
154    }
155
156    while (ret >= 0) {
157        if (!(frame = av_frame_alloc()))
158            return AVERROR(ENOMEM);
159
160        ret = avcodec_receive_frame(decoder_ctx, frame);
161        if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {
162            av_frame_free(&frame);
163            return 0;
164        } else if (ret < 0) {
165            fprintf(stderr, "Error while decoding. Error code: %s\n", av_err2str(ret));
166            goto fail;
167        }
168
169        if (!initialized) {
170            /* we need to ref hw_frames_ctx of decoder to initialize encoder's codec.
171               Only after we get a decoded frame, can we obtain its hw_frames_ctx */
172            encoder_ctx->hw_frames_ctx = av_buffer_ref(decoder_ctx->hw_frames_ctx);
173            if (!encoder_ctx->hw_frames_ctx) {
174                ret = AVERROR(ENOMEM);
175                goto fail;
176            }
177            /* set AVCodecContext Parameters for encoder, here we keep them stay
178             * the same as decoder.
179             * xxx: now the sample can't handle resolution change case.
180             */
181            encoder_ctx->time_base = av_inv_q(decoder_ctx->framerate);
182            encoder_ctx->pix_fmt   = AV_PIX_FMT_VAAPI;
183            encoder_ctx->width     = decoder_ctx->width;
184            encoder_ctx->height    = decoder_ctx->height;
185
186            if ((ret = avcodec_open2(encoder_ctx, enc_codec, NULL)) < 0) {
187                fprintf(stderr, "Failed to open encode codec. Error code: %s\n",
188                        av_err2str(ret));
189                goto fail;
190            }
191
192            if (!(ost = avformat_new_stream(ofmt_ctx, enc_codec))) {
193                fprintf(stderr, "Failed to allocate stream for output format.\n");
194                ret = AVERROR(ENOMEM);
195                goto fail;
196            }
197
198            ost->time_base = encoder_ctx->time_base;
199            ret = avcodec_parameters_from_context(ost->codecpar, encoder_ctx);
200            if (ret < 0) {
201                fprintf(stderr, "Failed to copy the stream parameters. "
202                        "Error code: %s\n", av_err2str(ret));
203                goto fail;
204            }
205
206            /* write the stream header */
207            if ((ret = avformat_write_header(ofmt_ctx, NULL)) < 0) {
208                fprintf(stderr, "Error while writing stream header. "
209                        "Error code: %s\n", av_err2str(ret));
210                goto fail;
211            }
212
213            initialized = 1;
214        }
215
216        if ((ret = encode_write(pkt, frame)) < 0)
217            fprintf(stderr, "Error during encoding and writing.\n");
218
219fail:
220        av_frame_free(&frame);
221        if (ret < 0)
222            return ret;
223    }
224    return 0;
225}
226
227int main(int argc, char **argv)
228{
229    const AVCodec *enc_codec;
230    int ret = 0;
231    AVPacket *dec_pkt;
232
233    if (argc != 4) {
234        fprintf(stderr, "Usage: %s <input file> <encode codec> <output file>\n"
235                "The output format is guessed according to the file extension.\n"
236                "\n", argv[0]);
237        return -1;
238    }
239
240    ret = av_hwdevice_ctx_create(&hw_device_ctx, AV_HWDEVICE_TYPE_VAAPI, NULL, NULL, 0);
241    if (ret < 0) {
242        fprintf(stderr, "Failed to create a VAAPI device. Error code: %s\n", av_err2str(ret));
243        return -1;
244    }
245
246    dec_pkt = av_packet_alloc();
247    if (!dec_pkt) {
248        fprintf(stderr, "Failed to allocate decode packet\n");
249        goto end;
250    }
251
252    if ((ret = open_input_file(argv[1])) < 0)
253        goto end;
254
255    if (!(enc_codec = avcodec_find_encoder_by_name(argv[2]))) {
256        fprintf(stderr, "Could not find encoder '%s'\n", argv[2]);
257        ret = -1;
258        goto end;
259    }
260
261    if ((ret = (avformat_alloc_output_context2(&ofmt_ctx, NULL, NULL, argv[3]))) < 0) {
262        fprintf(stderr, "Failed to deduce output format from file extension. Error code: "
263                "%s\n", av_err2str(ret));
264        goto end;
265    }
266
267    if (!(encoder_ctx = avcodec_alloc_context3(enc_codec))) {
268        ret = AVERROR(ENOMEM);
269        goto end;
270    }
271
272    ret = avio_open(&ofmt_ctx->pb, argv[3], AVIO_FLAG_WRITE);
273    if (ret < 0) {
274        fprintf(stderr, "Cannot open output file. "
275                "Error code: %s\n", av_err2str(ret));
276        goto end;
277    }
278
279    /* read all packets and only transcoding video */
280    while (ret >= 0) {
281        if ((ret = av_read_frame(ifmt_ctx, dec_pkt)) < 0)
282            break;
283
284        if (video_stream == dec_pkt->stream_index)
285            ret = dec_enc(dec_pkt, enc_codec);
286
287        av_packet_unref(dec_pkt);
288    }
289
290    /* flush decoder */
291    av_packet_unref(dec_pkt);
292    ret = dec_enc(dec_pkt, enc_codec);
293
294    /* flush encoder */
295    ret = encode_write(dec_pkt, NULL);
296
297    /* write the trailer for output stream */
298    av_write_trailer(ofmt_ctx);
299
300end:
301    avformat_close_input(&ifmt_ctx);
302    avformat_close_input(&ofmt_ctx);
303    avcodec_free_context(&decoder_ctx);
304    avcodec_free_context(&encoder_ctx);
305    av_buffer_unref(&hw_device_ctx);
306    av_packet_free(&dec_pkt);
307    return ret;
308}
309