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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 {
36  AVFrame *picture[2]; /* pictures array */
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 ||
75  dst_data[1] = src_data[1];
76 }
77 
79 {
81  MJpegDecodeContext *jpg = &s->jpg;
82  int ret;
83 
84  jpg->picture_ptr = NULL;
85  av_frame_free(&s->picture[0]);
86  av_frame_free(&s->picture[1]);
87  ret = avcodec_close(s->avctx);
88  av_freep(&s->avctx);
89  return ret;
90 }
91 
93 {
95  AVCodec *codec;
96  AVDictionary *thread_opt = NULL;
97  int ret = 0;
98 
99  s->frames_per_jpeg = 0;
100 
101  s->picture[0] = av_frame_alloc();
102  if (!s->picture[0])
103  return AVERROR(ENOMEM);
104 
105  s->picture[1] = av_frame_alloc();
106  if (!s->picture[1]) {
107  av_frame_free(&s->picture[0]);
108  return AVERROR(ENOMEM);
109  }
110 
111  s->jpg.picture_ptr = s->picture[0];
112 
113  if (avctx->extradata_size >= 4)
114  s->frames_per_jpeg = AV_RL32(avctx->extradata);
115 
116  if (s->frames_per_jpeg <= 0) {
117  av_log(avctx, AV_LOG_ERROR, "Invalid number of frames per jpeg.\n");
118  ret = -1;
119  }
120 
122  if (!codec) {
123  av_log(avctx, AV_LOG_ERROR, "MJPEG codec not found\n");
124  ret = -1;
125  }
126 
127  s->avctx = avcodec_alloc_context3(codec);
128 
129  av_dict_set(&thread_opt, "threads", "1", 0);
130  s->avctx->refcounted_frames = 1;
131  s->avctx->flags = avctx->flags;
132  s->avctx->idct_algo = avctx->idct_algo;
133  if (ff_codec_open2_recursive(s->avctx, codec, &thread_opt) < 0) {
134  av_log(avctx, AV_LOG_ERROR, "MJPEG codec failed to open\n");
135  ret = -1;
136  }
137  av_dict_free(&thread_opt);
138 
139  if (ret < 0)
140  smvjpeg_decode_end(avctx);
141  return ret;
142 }
143 
144 static int smvjpeg_decode_frame(AVCodecContext *avctx, void *data, int *data_size,
145  AVPacket *avpkt)
146 {
147  const AVPixFmtDescriptor *desc;
148  SMVJpegDecodeContext *s = avctx->priv_data;
149  AVFrame* mjpeg_data = s->picture[0];
150  int i, cur_frame = 0, ret = 0;
151 
152  cur_frame = avpkt->pts % s->frames_per_jpeg;
153 
154  /* Are we at the start of a block? */
155  if (!cur_frame) {
156  av_frame_unref(mjpeg_data);
157  ret = avcodec_decode_video2(s->avctx, mjpeg_data, &s->mjpeg_data_size, avpkt);
158  } else if (!s->mjpeg_data_size)
159  return AVERROR(EINVAL);
160 
161  desc = av_pix_fmt_desc_get(s->avctx->pix_fmt);
162  if (desc && mjpeg_data->height % (s->frames_per_jpeg << desc->log2_chroma_h)) {
163  av_log(avctx, AV_LOG_ERROR, "Invalid height\n");
164  return AVERROR_INVALIDDATA;
165  }
166 
167  /*use the last lot... */
168  *data_size = s->mjpeg_data_size;
169 
170  avctx->pix_fmt = s->avctx->pix_fmt;
171 
172  /* We shouldn't get here if frames_per_jpeg <= 0 because this was rejected
173  in init */
174  ret = ff_set_dimensions(avctx, mjpeg_data->width, mjpeg_data->height / s->frames_per_jpeg);
175  if (ret < 0) {
176  av_log(s, AV_LOG_ERROR, "Failed to set dimensions\n");
177  return ret;
178  }
179 
180  if (*data_size) {
181  s->picture[1]->extended_data = NULL;
182  s->picture[1]->width = avctx->width;
183  s->picture[1]->height = avctx->height;
184  s->picture[1]->format = avctx->pix_fmt;
185  /* ff_init_buffer_info(avctx, &s->picture[1]); */
186  smv_img_pnt(s->picture[1]->data, mjpeg_data->data, mjpeg_data->linesize,
187  avctx->pix_fmt, avctx->width, avctx->height, cur_frame);
188  for (i = 0; i < AV_NUM_DATA_POINTERS; i++)
189  s->picture[1]->linesize[i] = mjpeg_data->linesize[i];
190 
191  ret = av_frame_ref(data, s->picture[1]);
192  }
193 
194  return ret;
195 }
196 
197 static const AVClass smvjpegdec_class = {
198  .class_name = "SMVJPEG decoder",
199  .item_name = av_default_item_name,
200  .version = LIBAVUTIL_VERSION_INT,
201 };
202 
204  .name = "smvjpeg",
205  .long_name = NULL_IF_CONFIG_SMALL("SMV JPEG"),
206  .type = AVMEDIA_TYPE_VIDEO,
207  .id = AV_CODEC_ID_SMVJPEG,
208  .priv_data_size = sizeof(SMVJpegDecodeContext),
210  .close = smvjpeg_decode_end,
212  .priv_class = &smvjpegdec_class,
213 };