WebM Codec SDK: simple_encoder

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simple_encoder
1 /*
2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 // Simple Encoder
12 // ==============
13 //
14 // This is an example of a simple encoder loop. It takes an input file in
15 // YV12 format, passes it through the encoder, and writes the compressed
16 // frames to disk in IVF format. Other decoder examples build upon this
17 // one.
18 //
19 // The details of the IVF format have been elided from this example for
20 // simplicity of presentation, as IVF files will not generally be used by
21 // your application. In general, an IVF file consists of a file header,
22 // followed by a variable number of frames. Each frame consists of a frame
23 // header followed by a variable length payload. The length of the payload
24 // is specified in the first four bytes of the frame header. The payload is
25 // the raw compressed data.
26 //
27 // Standard Includes
28 // -----------------
29 // For encoders, you only have to include `vpx_encoder.h` and then any
30 // header files for the specific codecs you use. In this case, we're using
31 // vp8.
32 //
33 // Getting The Default Configuration
34 // ---------------------------------
35 // Encoders have the notion of "usage profiles." For example, an encoder
36 // may want to publish default configurations for both a video
37 // conferencing application and a best quality offline encoder. These
38 // obviously have very different default settings. Consult the
39 // documentation for your codec to see if it provides any default
40 // configurations. All codecs provide a default configuration, number 0,
41 // which is valid for material in the vacinity of QCIF/QVGA.
42 //
43 // Updating The Configuration
44 // ---------------------------------
45 // Almost all applications will want to update the default configuration
46 // with settings specific to their usage. Here we set the width and height
47 // of the video file to that specified on the command line. We also scale
48 // the default bitrate based on the ratio between the default resolution
49 // and the resolution specified on the command line.
50 //
51 // Initializing The Codec
52 // ----------------------
53 // The encoder is initialized by the following code.
54 //
55 // Encoding A Frame
56 // ----------------
57 // The frame is read as a continuous block (size width * height * 3 / 2)
58 // from the input file. If a frame was read (the input file has not hit
59 // EOF) then the frame is passed to the encoder. Otherwise, a NULL
60 // is passed, indicating the End-Of-Stream condition to the encoder. The
61 // `frame_cnt` is reused as the presentation time stamp (PTS) and each
62 // frame is shown for one frame-time in duration. The flags parameter is
63 // unused in this example. The deadline is set to VPX_DL_REALTIME to
64 // make the example run as quickly as possible.
65
66 // Forced Keyframes
67 // ----------------
68 // Keyframes can be forced by setting the VPX_EFLAG_FORCE_KF bit of the
69 // flags passed to `vpx_codec_control()`. In this example, we force a
70 // keyframe every <keyframe-interval> frames. Note, the output stream can
71 // contain additional keyframes beyond those that have been forced using the
72 // VPX_EFLAG_FORCE_KF flag because of automatic keyframe placement by the
73 // encoder.
74 //
75 // Processing The Encoded Data
76 // ---------------------------
77 // Each packet of type `VPX_CODEC_CX_FRAME_PKT` contains the encoded data
78 // for this frame. We write a IVF frame header, followed by the raw data.
79 //
80 // Cleanup
81 // -------
82 // The `vpx_codec_destroy` call frees any memory allocated by the codec.
83 //
84 // Error Handling
85 // --------------
86 // This example does not special case any error return codes. If there was
87 // an error, a descriptive message is printed and the program exits. With
88 // few exeptions, vpx_codec functions return an enumerated error status,
89 // with the value `0` indicating success.
90 //
91 // Error Resiliency Features
92 // -------------------------
93 // Error resiliency is controlled by the g_error_resilient member of the
94 // configuration structure. Use the `decode_with_drops` example to decode with
95 // frames 5-10 dropped. Compare the output for a file encoded with this example
96 // versus one encoded with the `simple_encoder` example.
97
98 #include <stdio.h>
99 #include <stdlib.h>
100 #include <string.h>
101
102 #include "vpx/vpx_encoder.h"
103
104 #include "../tools_common.h"
105 #include "../video_writer.h"
106
107 static const char *exec_name;
108
109 void usage_exit(void) {
110 fprintf(stderr,
111 "Usage: %s <codec> <width> <height> <infile> <outfile> "
112 "<keyframe-interval> [<error-resilient>]\nSee comments in "
113 "simple_encoder.c for more information.\n",
114 exec_name);
115 exit(EXIT_FAILURE);
116 }
117
118 static int encode_frame(vpx_codec_ctx_t *codec,
119 vpx_image_t *img,
120 int frame_index,
121 int flags,
122 VpxVideoWriter *writer) {
123 int got_pkts = 0;
124 vpx_codec_iter_t iter = NULL;
125 const vpx_codec_cx_pkt_t *pkt = NULL;
126 const vpx_codec_err_t res = vpx_codec_encode(codec, img, frame_index, 1,
127 flags, VPX_DL_GOOD_QUALITY);
128 if (res != VPX_CODEC_OK)
129 die_codec(codec, "Failed to encode frame");
130
131 while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) {
132 got_pkts = 1;
133
134 if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) {
135 const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0;
136 if (!vpx_video_writer_write_frame(writer,
137 pkt->data.frame.buf,
138 pkt->data.frame.sz,
139 pkt->data.frame.pts)) {
140 die_codec(codec, "Failed to write compressed frame");
141 }
142 printf(keyframe ? "K" : ".");
143 fflush(stdout);
144 }
145 }
146
147 return got_pkts;
148 }
149
150 int main(int argc, char **argv) {
151 FILE *infile = NULL;
152 vpx_codec_ctx_t codec;
153 vpx_codec_enc_cfg_t cfg;
154 int frame_count = 0;
155 vpx_image_t raw;
156 vpx_codec_err_t res;
157 VpxVideoInfo info = {0};
158 VpxVideoWriter *writer = NULL;
159 const VpxInterface *encoder = NULL;
160 const int fps = 30; // TODO(dkovalev) add command line argument
161 const int bitrate = 200; // kbit/s TODO(dkovalev) add command line argument
162 int keyframe_interval = 0;
163
164 // TODO(dkovalev): Add some simple command line parsing code to make the
165 // command line more flexible.
166 const char *codec_arg = NULL;
167 const char *width_arg = NULL;
168 const char *height_arg = NULL;
169 const char *infile_arg = NULL;
170 const char *outfile_arg = NULL;
171 const char *keyframe_interval_arg = NULL;
172
173 exec_name = argv[0];
174
175 if (argc < 7)
176 die("Invalid number of arguments");
177
178 codec_arg = argv[1];
179 width_arg = argv[2];
180 height_arg = argv[3];
181 infile_arg = argv[4];
182 outfile_arg = argv[5];
183 keyframe_interval_arg = argv[6];
184
185 encoder = get_vpx_encoder_by_name(codec_arg);
186 if (!encoder)
187 die("Unsupported codec.");
188
189 info.codec_fourcc = encoder->fourcc;
190 info.frame_width = strtol(width_arg, NULL, 0);
191 info.frame_height = strtol(height_arg, NULL, 0);
192 info.time_base.numerator = 1;
193 info.time_base.denominator = fps;
194
195 if (info.frame_width <= 0 ||
196 info.frame_height <= 0 ||
197 (info.frame_width % 2) != 0 ||
198 (info.frame_height % 2) != 0) {
199 die("Invalid frame size: %dx%d", info.frame_width, info.frame_height);
200 }
201
202 if (!vpx_img_alloc(&raw, VPX_IMG_FMT_I420, info.frame_width,
203 info.frame_height, 1)) {
204 die("Failed to allocate image.");
205 }
206
207 keyframe_interval = strtol(keyframe_interval_arg, NULL, 0);
208 if (keyframe_interval < 0)
209 die("Invalid keyframe interval value.");
210
211 printf("Using %s\n", vpx_codec_iface_name(encoder->codec_interface()));
212
213 res = vpx_codec_enc_config_default(encoder->codec_interface(), &cfg, 0);
214 if (res)
215 die_codec(&codec, "Failed to get default codec config.");
216
217 cfg.g_w = info.frame_width;
218 cfg.g_h = info.frame_height;
219 cfg.g_timebase.num = info.time_base.numerator;
220 cfg.g_timebase.den = info.time_base.denominator;
221 cfg.rc_target_bitrate = bitrate;
222 cfg.g_error_resilient = argc > 7 ? strtol(argv[7], NULL, 0) : 0;
223
224 writer = vpx_video_writer_open(outfile_arg, kContainerIVF, &info);
225 if (!writer)
226 die("Failed to open %s for writing.", outfile_arg);
227
228 if (!(infile = fopen(infile_arg, "rb")))
229 die("Failed to open %s for reading.", infile_arg);
230
231 if (vpx_codec_enc_init(&codec, encoder->codec_interface(), &cfg, 0))
232 die_codec(&codec, "Failed to initialize encoder");
233
234 // Encode frames.
235 while (vpx_img_read(&raw, infile)) {
236 int flags = 0;
237 if (keyframe_interval > 0 && frame_count % keyframe_interval == 0)
238 flags |= VPX_EFLAG_FORCE_KF;
239 encode_frame(&codec, &raw, frame_count++, flags, writer);
240 }
241
242 // Flush encoder.
243 while (encode_frame(&codec, NULL, -1, 0, writer)) {};
244
245 printf("\n");
246 fclose(infile);
247 printf("Processed %d frames.\n", frame_count);
248
249 vpx_img_free(&raw);
250 if (vpx_codec_destroy(&codec))
251 die_codec(&codec, "Failed to destroy codec.");
252
253 vpx_video_writer_close(writer);
254
255 return EXIT_SUCCESS;
256 }
vpx_image
Image Descriptor.
Definition: vpx_image.h:88
vpx_encoder.h
Describes the encoder algorithm interface to applications.
vpx_codec_iface_name
const char * vpx_codec_iface_name(vpx_codec_iface_t *iface)
Return the name for a given interface.
vpx_codec_enc_cfg::g_timebase
struct vpx_rational g_timebase
Stream timebase units.
Definition: vpx_encoder.h:397
vpx_rational::den
int den
Definition: vpx_encoder.h:261
vpx_codec_encode
vpx_codec_err_t vpx_codec_encode(vpx_codec_ctx_t *ctx, const vpx_image_t *img, vpx_codec_pts_t pts, unsigned long duration, vpx_enc_frame_flags_t flags, unsigned long deadline)
Encode a frame.
vpx_codec_enc_cfg
Encoder configuration structure.
Definition: vpx_encoder.h:314
vpx_codec_cx_pkt
Encoder output packet.
Definition: vpx_encoder.h:195
vpx_codec_cx_pkt::frame
struct vpx_codec_cx_pkt::@1::@2 frame
vpx_img_alloc
vpx_image_t * vpx_img_alloc(vpx_image_t *img, vpx_img_fmt_t fmt, unsigned int d_w, unsigned int d_h, unsigned int align)
Open a descriptor, allocating storage for the underlying image.
VPX_IMG_FMT_I420
Definition: vpx_image.h:56
vpx_codec_enc_cfg::g_w
unsigned int g_w
Width of the frame.
Definition: vpx_encoder.h:357
vpx_codec_enc_cfg::g_h
unsigned int g_h
Height of the frame.
Definition: vpx_encoder.h:367
vpx_codec_cx_pkt::kind
enum vpx_codec_cx_pkt_kind kind
Definition: vpx_encoder.h:196
VPX_CODEC_OK
Operation completed without error.
Definition: vpx_codec.h:91
vpx_img_free
void vpx_img_free(vpx_image_t *img)
Close an image descriptor.
vpx_codec_enc_cfg::rc_target_bitrate
unsigned int rc_target_bitrate
Target data rate.
Definition: vpx_encoder.h:525
vpx_rational::num
int num
Definition: vpx_encoder.h:260
VPX_DL_GOOD_QUALITY
#define VPX_DL_GOOD_QUALITY
Definition: vpx_encoder.h:914
vpx_codec_enc_init
#define vpx_codec_enc_init(ctx, iface, cfg, flags)
Convenience macro for vpx_codec_enc_init_ver()
Definition: vpx_encoder.h:813
vpx_codec_err_t
vpx_codec_err_t
Algorithm return codes.
Definition: vpx_codec.h:89
vpx_codec_get_cx_data
const vpx_codec_cx_pkt_t * vpx_codec_get_cx_data(vpx_codec_ctx_t *ctx, vpx_codec_iter_t *iter)
Encoded data iterator.
vpx_codec_cx_pkt::data
union vpx_codec_cx_pkt::@1 data
vpx_codec_enc_config_default
vpx_codec_err_t vpx_codec_enc_config_default(vpx_codec_iface_t *iface, vpx_codec_enc_cfg_t *cfg, unsigned int reserved)
Get a default configuration.
vpx_codec_destroy
vpx_codec_err_t vpx_codec_destroy(vpx_codec_ctx_t *ctx)
Destroy a codec instance.
VPX_FRAME_IS_KEY
#define VPX_FRAME_IS_KEY
Definition: vpx_encoder.h:130
VPX_EFLAG_FORCE_KF
#define VPX_EFLAG_FORCE_KF
Definition: vpx_encoder.h:305
vpx_codec_iter_t
const void * vpx_codec_iter_t
Iterator.
Definition: vpx_codec.h:188
VPX_CODEC_CX_FRAME_PKT
Definition: vpx_encoder.h:176
vpx_codec_enc_cfg::g_error_resilient
vpx_codec_er_flags_t g_error_resilient
Enable error resilient modes.
Definition: vpx_encoder.h:406
vpx_codec_ctx
Codec context structure.
Definition: vpx_codec.h:199