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Diffstat (limited to 'ecp/test/vid/enc.c')
-rw-r--r-- | ecp/test/vid/enc.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/ecp/test/vid/enc.c b/ecp/test/vid/enc.c new file mode 100644 index 0000000..34d0be8 --- /dev/null +++ b/ecp/test/vid/enc.c @@ -0,0 +1,168 @@ +/* + * Copyright (c) 2010 The WebM project authors. All Rights Reserved. + * + * Use of this source code is governed by a BSD-style license + * that can be found in the LICENSE file in the root of the source + * tree. An additional intellectual property rights grant can be found + * in the file PATENTS. All contributing project authors may + * be found in the AUTHORS file in the root of the source tree. + */ + +// Simple Encoder +// ============== +// +// This is an example of a simple encoder loop. It takes an input file in +// YV12 format, passes it through the encoder, and writes the compressed +// frames to disk in IVF format. Other decoder examples build upon this +// one. +// +// The details of the IVF format have been elided from this example for +// simplicity of presentation, as IVF files will not generally be used by +// your application. In general, an IVF file consists of a file header, +// followed by a variable number of frames. Each frame consists of a frame +// header followed by a variable length payload. The length of the payload +// is specified in the first four bytes of the frame header. The payload is +// the raw compressed data. +// +// Standard Includes +// ----------------- +// For encoders, you only have to include `vpx_encoder.h` and then any +// header files for the specific codecs you use. In this case, we're using +// vp8. +// +// Getting The Default Configuration +// --------------------------------- +// Encoders have the notion of "usage profiles." For example, an encoder +// may want to publish default configurations for both a video +// conferencing application and a best quality offline encoder. These +// obviously have very different default settings. Consult the +// documentation for your codec to see if it provides any default +// configurations. All codecs provide a default configuration, number 0, +// which is valid for material in the vacinity of QCIF/QVGA. +// +// Updating The Configuration +// --------------------------------- +// Almost all applications will want to update the default configuration +// with settings specific to their usage. Here we set the width and height +// of the video file to that specified on the command line. We also scale +// the default bitrate based on the ratio between the default resolution +// and the resolution specified on the command line. +// +// Initializing The Codec +// ---------------------- +// The encoder is initialized by the following code. +// +// Encoding A Frame +// ---------------- +// The frame is read as a continuous block (size width * height * 3 / 2) +// from the input file. If a frame was read (the input file has not hit +// EOF) then the frame is passed to the encoder. Otherwise, a NULL +// is passed, indicating the End-Of-Stream condition to the encoder. The +// `frame_cnt` is reused as the presentation time stamp (PTS) and each +// frame is shown for one frame-time in duration. The flags parameter is +// unused in this example. The deadline is set to VPX_DL_REALTIME to +// make the example run as quickly as possible. + +// Forced Keyframes +// ---------------- +// Keyframes can be forced by setting the VPX_EFLAG_FORCE_KF bit of the +// flags passed to `vpx_codec_control()`. In this example, we force a +// keyframe every <keyframe-interval> frames. Note, the output stream can +// contain additional keyframes beyond those that have been forced using the +// VPX_EFLAG_FORCE_KF flag because of automatic keyframe placement by the +// encoder. +// +// Processing The Encoded Data +// --------------------------- +// Each packet of type `VPX_CODEC_CX_FRAME_PKT` contains the encoded data +// for this frame. We write a IVF frame header, followed by the raw data. +// +// Cleanup +// ------- +// The `vpx_codec_destroy` call frees any memory allocated by the codec. +// +// Error Handling +// -------------- +// This example does not special case any error return codes. If there was +// an error, a descriptive message is printed and the program exits. With +// few exeptions, vpx_codec functions return an enumerated error status, +// with the value `0` indicating success. +// +// Error Resiliency Features +// ------------------------- +// Error resiliency is controlled by the g_error_resilient member of the +// configuration structure. Use the `decode_with_drops` example to decode with +// frames 5-10 dropped. Compare the output for a file encoded with this example +// versus one encoded with the `simple_encoder` example. + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "enc.h" +#include "server.h" + +int vpx_encode_frame(vpx_codec_ctx_t *codec, vpx_image_t *img, int frame_index, int flags) { + int got_pkts = 0; + vpx_codec_iter_t iter = NULL; + const vpx_codec_cx_pkt_t *pkt = NULL; + const vpx_codec_err_t res = + vpx_codec_encode(codec, img, frame_index, 1, flags, VPX_DL_REALTIME); + if (res != VPX_CODEC_OK) die_codec(codec, "Failed to encode frame"); + + while ((pkt = vpx_codec_get_cx_data(codec, &iter)) != NULL) { + got_pkts = 1; + + if (pkt->kind == VPX_CODEC_CX_FRAME_PKT) { + const int keyframe = (pkt->data.frame.flags & VPX_FRAME_IS_KEY) != 0; + if (send_frame(pkt->data.frame.buf, pkt->data.frame.sz, pkt->data.frame.pts) < 0) { + die_codec(codec, "Failed to write compressed frame"); + } + fprintf(stderr, keyframe ? "K" : "."); + fflush(stdout); + } + } + + return got_pkts; +} + + +void vpx_open(const char *codec_arg, int width, int height, int fps, int bitrate, vpx_codec_er_flags_t err_resilient, vpx_codec_ctx_t *codec, vpx_image_t *raw) { + vpx_codec_enc_cfg_t cfg; + vpx_codec_err_t res; + + const VpxInterface *encoder = get_vpx_encoder_by_name(codec_arg); + if (!encoder) die_codec(NULL, "Unsupported codec."); + + fprintf(stderr, "Using %s\n", vpx_codec_iface_name(encoder->codec_interface())); + + if (!vpx_img_alloc(raw, VPX_IMG_FMT_I420, width, height, 1)) + die_codec(NULL, "Failed to allocate image."); + + res = vpx_codec_enc_config_default(encoder->codec_interface(), &cfg, 0); + if (res) die_codec(NULL, "Failed to get default codec config."); + + cfg.g_w = width; + cfg.g_h = height; + cfg.g_timebase.num = 1; + cfg.g_timebase.den = fps; + cfg.rc_target_bitrate = bitrate; + cfg.g_error_resilient = err_resilient; + cfg.g_lag_in_frames = 0; + cfg.rc_end_usage = VPX_CBR; + + if (vpx_codec_enc_init(codec, encoder->codec_interface(), &cfg, 0)) + die_codec(codec, "Failed to initialize encoder"); + + if (vpx_codec_control(codec, VP8E_SET_CPUUSED, 8)) + die_codec(codec, "Failed to initialize cpuused"); +} + +void vpx_close(vpx_codec_ctx_t *codec, vpx_image_t *raw) { + // Flush encoder. + while (vpx_encode_frame(codec, NULL, -1, 0)) { + } + + vpx_img_free(raw); + if (vpx_codec_destroy(codec)) die_codec(codec, "Failed to destroy codec."); +} |