FFmpeg: libavcodec/smvjpegdec.c Source File

FFmpeg
smvjpegdec.c
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1 /*
2  * SMV JPEG decoder
3  * Copyright (c) 2013 Ash Hughes
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  * SMV JPEG decoder.
25  */
26 
27 // #define DEBUG
28 #include "avcodec.h"
29 #include "libavutil/opt.h"
30 #include "libavutil/imgutils.h"
31 #include "mjpegdec.h"
32 #include "internal.h"
33 
34  typedef struct SMVJpegDecodeContext {
35   MJpegDecodeContext jpg;
36   AVFrame *picture[2]; /* pictures array */
37   AVCodecContext* avctx;
38   int frames_per_jpeg;
39   int mjpeg_data_size;
40 } SMVJpegDecodeContext;
41 
42  static inline void smv_img_pnt_plane(uint8_t **dst, uint8_t *src,
43  int src_linesize, int height, int nlines)
44 {
45  if (!dst || !src)
46  return;
47  src += (nlines) * src_linesize * height;
48  *dst = src;
49 }
50 
51  static inline void smv_img_pnt(uint8_t *dst_data[4], uint8_t *src_data[4],
52  const int src_linesizes[4],
53  enum PixelFormat pix_fmt, int width, int height,
54  int nlines)
55 {
56  const AVPixFmtDescriptor *desc = av_pix_fmt_desc_get(pix_fmt);
57  int i, planes_nb = 0;
58 
59  if (desc->flags & AV_PIX_FMT_FLAG_HWACCEL)
60  return;
61 
62  for (i = 0; i < desc->nb_components; i++)
63  planes_nb = FFMAX(planes_nb, desc->comp[i].plane + 1);
64 
65  for (i = 0; i < planes_nb; i++) {
66  int h = height;
67  if (i == 1 || i == 2) {
68  h = FF_CEIL_RSHIFT(height, desc->log2_chroma_h);
69  }
70  smv_img_pnt_plane(&dst_data[i], src_data[i],
71  src_linesizes[i], h, nlines);
72  }
73  if (desc->flags & AV_PIX_FMT_FLAG_PAL ||
74  desc->flags & AV_PIX_FMT_FLAG_PSEUDOPAL)
75  dst_data[1] = src_data[1];
76 }
77 
78  static av_cold int smvjpeg_decode_init(AVCodecContext *avctx)
79 {
80  SMVJpegDecodeContext *s = avctx->priv_data;
81  AVCodec *codec;
82  AVDictionary *thread_opt = NULL;
83  int ret = 0;
84 
85  s->frames_per_jpeg = 0;
86 
87  s->picture[0] = av_frame_alloc();
88  if (!s->picture[0])
89  return AVERROR(ENOMEM);
90 
91  s->picture[1] = av_frame_alloc();
92  if (!s->picture[1])
93  return AVERROR(ENOMEM);
94 
95  s->jpg.picture_ptr = s->picture[0];
96 
97  if (avctx->extradata_size >= 4)
98  s->frames_per_jpeg = AV_RL32(avctx->extradata);
99 
100  if (s->frames_per_jpeg <= 0) {
101  av_log(avctx, AV_LOG_ERROR, "Invalid number of frames per jpeg.\n");
102  ret = -1;
103  }
104 
105  codec = avcodec_find_decoder(AV_CODEC_ID_MJPEG);
106  if (!codec) {
107  av_log(avctx, AV_LOG_ERROR, "MJPEG codec not found\n");
108  ret = -1;
109  }
110 
111  s->avctx = avcodec_alloc_context3(codec);
112 
113  av_dict_set(&thread_opt, "threads", "1", 0);
114  s->avctx->refcounted_frames = 1;
115  s->avctx->flags = avctx->flags;
116  s->avctx->idct_algo = avctx->idct_algo;
117  if (ff_codec_open2_recursive(s->avctx, codec, &thread_opt) < 0) {
118  av_log(avctx, AV_LOG_ERROR, "MJPEG codec failed to open\n");
119  ret = -1;
120  }
121  av_dict_free(&thread_opt);
122 
123  return ret;
124 }
125 
126  static int smvjpeg_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
127  AVPacket *avpkt)
128 {
129  const AVPixFmtDescriptor *desc;
130  SMVJpegDecodeContext *s = avctx->priv_data;
131  AVFrame* mjpeg_data = s->picture[0];
132  int i, cur_frame = 0, ret = 0;
133 
134  cur_frame = avpkt->pts % s->frames_per_jpeg;
135 
136  /* Are we at the start of a block? */
137  if (!cur_frame) {
138  av_frame_unref(mjpeg_data);
139  ret = avcodec_decode_video2(s->avctx, mjpeg_data, &s->mjpeg_data_size, avpkt);
140  } else if (!s->mjpeg_data_size)
141  return AVERROR(EINVAL);
142 
143  desc = av_pix_fmt_desc_get(s->avctx->pix_fmt);
144  if (desc && mjpeg_data->height % (s->frames_per_jpeg << desc->log2_chroma_h)) {
145  av_log(avctx, AV_LOG_ERROR, "Invalid height\n");
146  return AVERROR_INVALIDDATA;
147  }
148 
149  /*use the last lot... */
150  *data_size = s->mjpeg_data_size;
151 
152  avctx->pix_fmt = s->avctx->pix_fmt;
153 
154  /* We shouldn't get here if frames_per_jpeg <= 0 because this was rejected
155  in init */
156  avcodec_set_dimensions(avctx, mjpeg_data->width,
157  mjpeg_data->height / s->frames_per_jpeg);
158 
159  if (*data_size) {
160  s->picture[1]->extended_data = NULL;
161  s->picture[1]->width = avctx->width;
162  s->picture[1]->height = avctx->height;
163  s->picture[1]->format = avctx->pix_fmt;
164  /* ff_init_buffer_info(avctx, &s->picture[1]); */
165  smv_img_pnt(s->picture[1]->data, mjpeg_data->data, mjpeg_data->linesize,
166  avctx->pix_fmt, avctx->width, avctx->height, cur_frame);
167  for (i = 0; i < AV_NUM_DATA_POINTERS; i++)
168  s->picture[1]->linesize[i] = mjpeg_data->linesize[i];
169 
170  ret = av_frame_ref(data, s->picture[1]);
171  }
172 
173  return ret;
174 }
175 
176  static av_cold int smvjpeg_decode_end(AVCodecContext *avctx)
177 {
178  SMVJpegDecodeContext *s = avctx->priv_data;
179  MJpegDecodeContext *jpg = &s->jpg;
180 
181  jpg->picture_ptr = NULL;
182  av_frame_free(&s->picture[0]);
183  av_frame_free(&s->picture[1]);
184  ff_codec_close_recursive(s->avctx);
185  av_freep(&s->avctx);
186  return 0;
187 }
188 
189  static const AVClass smvjpegdec_class = {
190  .class_name = "SMVJPEG decoder",
191  .item_name = av_default_item_name,
192  .version = LIBAVUTIL_VERSION_INT,
193 };
194 
195  AVCodec ff_smvjpeg_decoder = {
196  .name = "smvjpeg",
197  .long_name = NULL_IF_CONFIG_SMALL("SMV JPEG"),
198  .type = AVMEDIA_TYPE_VIDEO,
199  .id = AV_CODEC_ID_SMVJPEG,
200  .priv_data_size = sizeof(SMVJpegDecodeContext),
201  .init = smvjpeg_decode_init,
202  .close = smvjpeg_decode_end,
203  .decode = smvjpeg_decode_frame,
204  .priv_class = &smvjpegdec_class,
205 };
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