FFmpeg
libwebpenc_animencoder.c
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1 /*
2  * WebP encoding support via libwebp
3  * Copyright (c) 2015 Urvang Joshi
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * WebP encoder using libwebp (WebPAnimEncoder API)
25  */
26 
27 #include "config.h"
28 #include "libwebpenc_common.h"
29 
30 #include <webp/mux.h>
31 
32 typedef struct LibWebPAnimContext {
34  WebPAnimEncoder *enc; // the main AnimEncoder object
35  int64_t prev_frame_pts; // pts of the previously encoded frame.
36  int done; // If true, we have assembled the bitstream already
38 
40 {
42  if (!ret) {
43  LibWebPAnimContext *s = avctx->priv_data;
44  WebPAnimEncoderOptions enc_options = { { 0 } };
45  WebPAnimEncoderOptionsInit(&enc_options);
46  enc_options.verbose = av_log_get_level() >= AV_LOG_VERBOSE;
47  // TODO(urvang): Expose some options on command-line perhaps.
48  s->enc = WebPAnimEncoderNew(avctx->width, avctx->height, &enc_options);
49  if (!s->enc)
50  return AVERROR(EINVAL);
51  s->prev_frame_pts = -1;
52  s->done = 0;
53  }
54  return ret;
55 }
56 
58  const AVFrame *frame, int *got_packet) {
59  LibWebPAnimContext *s = avctx->priv_data;
60  int ret;
61 
62  if (!frame) {
63  if (s->done) { // Second flush: return empty package to denote finish.
64  *got_packet = 0;
65  return 0;
66  } else { // First flush: assemble bitstream and return it.
67  WebPData assembled_data = { 0 };
68  ret = WebPAnimEncoderAssemble(s->enc, &assembled_data);
69  if (ret) {
70  ret = ff_alloc_packet2(avctx, pkt, assembled_data.size, assembled_data.size);
71  if (ret < 0)
72  return ret;
73  memcpy(pkt->data, assembled_data.bytes, assembled_data.size);
74  s->done = 1;
75  pkt->flags |= AV_PKT_FLAG_KEY;
76  pkt->pts = pkt->dts = s->prev_frame_pts + 1;
77  *got_packet = 1;
78  return 0;
79  } else {
81  "WebPAnimEncoderAssemble() failed with error: %d\n",
82  VP8_ENC_ERROR_OUT_OF_MEMORY);
83  return AVERROR(ENOMEM);
84  }
85  }
86  } else {
87  int timestamp_ms;
88  WebPPicture *pic = NULL;
89  AVFrame *alt_frame = NULL;
90  ret = ff_libwebp_get_frame(avctx, &s->cc, frame, &alt_frame, &pic);
91  if (ret < 0)
92  goto end;
93 
94  timestamp_ms =
95  avctx->time_base.num * frame->pts * 1000 / avctx->time_base.den;
96  ret = WebPAnimEncoderAdd(s->enc, pic, timestamp_ms, &s->cc.config);
97  if (!ret) {
98  av_log(avctx, AV_LOG_ERROR,
99  "Encoding WebP frame failed with error: %d\n",
100  pic->error_code);
101  ret = ff_libwebp_error_to_averror(pic->error_code);
102  goto end;
103  }
104 
105  pkt->pts = pkt->dts = frame->pts;
106  s->prev_frame_pts = frame->pts; // Save for next frame.
107  ret = 0;
108  *got_packet = 1;
109 
110 end:
111  WebPPictureFree(pic);
112  av_freep(&pic);
113  av_frame_free(&alt_frame);
114  return ret;
115  }
116 }
117 
119 {
120  LibWebPAnimContext *s = avctx->priv_data;
121  av_frame_free(&s->cc.ref);
122  WebPAnimEncoderDelete(s->enc);
123 
124  return 0;
125 }
126 
127 static const AVClass class = {
128  .class_name = "libwebp_anim",
129  .item_name = av_default_item_name,
130  .option = options,
132 };
133 
135  .name = "libwebp_anim",
136  .long_name = NULL_IF_CONFIG_SMALL("libwebp WebP image"),
137  .type = AVMEDIA_TYPE_VIDEO,
138  .id = AV_CODEC_ID_WEBP,
139  .priv_data_size = sizeof(LibWebPAnimContext),
141  .encode2 = libwebp_anim_encode_frame,
142  .close = libwebp_anim_encode_close,
143  .capabilities = AV_CODEC_CAP_DELAY,
144  .pix_fmts = (const enum AVPixelFormat[]) {
148  },
149  .priv_class = &class,
150  .defaults = libwebp_defaults,
151  .wrapper_name = "libwebp",
152 };
#define NULL
Definition: coverity.c:32
AVCodec ff_libwebp_anim_encoder
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
static int libwebp_anim_encode_frame(AVCodecContext *avctx, AVPacket *pkt, const AVFrame *frame, int *got_packet)
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int num
Numerator.
Definition: rational.h:59
int size
Definition: avcodec.h:1478
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:191
LibWebPContextCommon cc
static AVPacket pkt
AVCodec.
Definition: avcodec.h:3481
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1688
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
#define AV_CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: avcodec.h:1006
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:32
planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
Definition: pixfmt.h:101
#define av_cold
Definition: attributes.h:82
static av_cold int end(AVCodecContext *avctx)
Definition: avrndec.c:90
int64_t pts
Presentation timestamp in time_base units (time when frame should be shown to user).
Definition: frame.h:388
uint8_t * data
Definition: avcodec.h:1477
#define AV_LOG_VERBOSE
Detailed information.
Definition: log.h:192
#define av_log(a,...)
#define AV_PKT_FLAG_KEY
The packet contains a keyframe.
Definition: avcodec.h:1509
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
WebP encoder using libwebp: common structs and methods.
void av_frame_free(AVFrame **frame)
Free the frame and any dynamically allocated objects in it, e.g.
Definition: frame.c:202
static av_cold int libwebp_anim_encode_init(AVCodecContext *avctx)
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
int av_log_get_level(void)
Get the current log level.
Definition: log.c:380
const char * name
Name of the codec implementation.
Definition: avcodec.h:3488
int ff_libwebp_get_frame(AVCodecContext *avctx, LibWebPContextCommon *s, const AVFrame *frame, AVFrame **alt_frame_ptr, WebPPicture **pic_ptr)
av_cold int ff_libwebp_encode_init_common(AVCodecContext *avctx)
int flags
A combination of AV_PKT_FLAG values.
Definition: avcodec.h:1483
int width
picture width / height.
Definition: avcodec.h:1738
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
#define s(width, name)
Definition: cbs_vp9.c:257
static const AVCodecDefault libwebp_defaults[]
int ff_libwebp_error_to_averror(int err)
main external API structure.
Definition: avcodec.h:1565
#define AV_PIX_FMT_RGB32
Definition: pixfmt.h:360
Describe the class of an AVClass context structure.
Definition: log.h:67
static enum AVPixelFormat pix_fmts[]
Definition: libkvazaar.c:275
planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
Definition: pixfmt.h:66
const OptionDef options[]
Definition: ffmpeg_opt.c:3364
int den
Denominator.
Definition: rational.h:60
void * priv_data
Definition: avcodec.h:1592
static int libwebp_anim_encode_close(AVCodecContext *avctx)
int64_t dts
Decompression timestamp in AVStream->time_base units; the time at which the packet is decompressed...
Definition: avcodec.h:1476
#define av_freep(p)
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later.That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another.Frame references ownership and permissions
AVPixelFormat
Pixel format.
Definition: pixfmt.h:64
This structure stores compressed data.
Definition: avcodec.h:1454
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: avcodec.h:1470