yading@10: /*
yading@10:  * MxPEG decoder
yading@10:  * Copyright (c) 2011 Anatoly Nenashev
yading@10:  *
yading@10:  * This file is part of FFmpeg.
yading@10:  *
yading@10:  * FFmpeg is free software; you can redistribute it and/or
yading@10:  * modify it under the terms of the GNU Lesser General Public
yading@10:  * License as published by the Free Software Foundation; either
yading@10:  * version 2.1 of the License, or (at your option) any later version.
yading@10:  *
yading@10:  * FFmpeg is distributed in the hope that it will be useful,
yading@10:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@10:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@10:  * Lesser General Public License for more details.
yading@10:  *
yading@10:  * You should have received a copy of the GNU Lesser General Public
yading@10:  * License along with FFmpeg; if not, write to the Free Software
yading@10:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@10:  */
yading@10: 
yading@10: 
yading@10: /**
yading@10:  * @file
yading@10:  * MxPEG decoder
yading@10:  */
yading@10: 
yading@10: #include "internal.h"
yading@10: #include "mjpeg.h"
yading@10: #include "mjpegdec.h"
yading@10: 
yading@10: typedef struct MXpegDecodeContext {
yading@10:     MJpegDecodeContext jpg;
yading@10:     AVFrame picture[2]; /* pictures array */
yading@10:     int picture_index; /* index of current picture */
yading@10:     int got_sof_data; /* true if SOF data successfully parsed */
yading@10:     int got_mxm_bitmask; /* true if MXM bitmask available */
yading@10:     uint8_t *mxm_bitmask; /* bitmask buffer */
yading@10:     unsigned bitmask_size; /* size of bitmask */
yading@10:     int has_complete_frame; /* true if has complete frame */
yading@10:     uint8_t *completion_bitmask; /* completion bitmask of macroblocks */
yading@10:     unsigned mb_width, mb_height; /* size of picture in MB's from MXM header */
yading@10: } MXpegDecodeContext;
yading@10: 
yading@10: static av_cold int mxpeg_decode_init(AVCodecContext *avctx)
yading@10: {
yading@10:     MXpegDecodeContext *s = avctx->priv_data;
yading@10: 
yading@10:     s->jpg.picture_ptr      = &s->picture[0];
yading@10:     return ff_mjpeg_decode_init(avctx);
yading@10: }
yading@10: 
yading@10: static int mxpeg_decode_app(MXpegDecodeContext *s,
yading@10:                             const uint8_t *buf_ptr, int buf_size)
yading@10: {
yading@10:     int len;
yading@10:     if (buf_size < 2)
yading@10:         return 0;
yading@10:     len = AV_RB16(buf_ptr);
yading@10:     skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int mxpeg_decode_mxm(MXpegDecodeContext *s,
yading@10:                             const uint8_t *buf_ptr, int buf_size)
yading@10: {
yading@10:     unsigned bitmask_size, mb_count;
yading@10:     int i;
yading@10: 
yading@10:     s->mb_width  = AV_RL16(buf_ptr+4);
yading@10:     s->mb_height = AV_RL16(buf_ptr+6);
yading@10:     mb_count = s->mb_width * s->mb_height;
yading@10: 
yading@10:     bitmask_size = (mb_count + 7) >> 3;
yading@10:     if (bitmask_size > buf_size - 12) {
yading@10:         av_log(s->jpg.avctx, AV_LOG_ERROR,
yading@10:                "MXM bitmask is not complete\n");
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10: 
yading@10:     if (s->bitmask_size != bitmask_size) {
yading@10:         s->bitmask_size = 0;
yading@10:         av_freep(&s->mxm_bitmask);
yading@10:         s->mxm_bitmask = av_malloc(bitmask_size);
yading@10:         if (!s->mxm_bitmask) {
yading@10:             av_log(s->jpg.avctx, AV_LOG_ERROR,
yading@10:                    "MXM bitmask memory allocation error\n");
yading@10:             return AVERROR(ENOMEM);
yading@10:         }
yading@10: 
yading@10:         av_freep(&s->completion_bitmask);
yading@10:         s->completion_bitmask = av_mallocz(bitmask_size);
yading@10:         if (!s->completion_bitmask) {
yading@10:             av_log(s->jpg.avctx, AV_LOG_ERROR,
yading@10:                    "Completion bitmask memory allocation error\n");
yading@10:             return AVERROR(ENOMEM);
yading@10:         }
yading@10: 
yading@10:         s->bitmask_size = bitmask_size;
yading@10:     }
yading@10: 
yading@10:     memcpy(s->mxm_bitmask, buf_ptr + 12, bitmask_size);
yading@10:     s->got_mxm_bitmask = 1;
yading@10: 
yading@10:     if (!s->has_complete_frame) {
yading@10:         uint8_t completion_check = 0xFF;
yading@10:         for (i = 0; i < bitmask_size; ++i) {
yading@10:             s->completion_bitmask[i] |= s->mxm_bitmask[i];
yading@10:             completion_check &= s->completion_bitmask[i];
yading@10:         }
yading@10:         s->has_complete_frame = !(completion_check ^ 0xFF);
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int mxpeg_decode_com(MXpegDecodeContext *s,
yading@10:                             const uint8_t *buf_ptr, int buf_size)
yading@10: {
yading@10:     int len, ret = 0;
yading@10:     if (buf_size < 2)
yading@10:         return 0;
yading@10:     len = AV_RB16(buf_ptr);
yading@10:     if (len > 14 && len <= buf_size && !strncmp(buf_ptr + 2, "MXM", 3)) {
yading@10:         ret = mxpeg_decode_mxm(s, buf_ptr + 2, len - 2);
yading@10:     }
yading@10:     skip_bits(&s->jpg.gb, 8*FFMIN(len,buf_size));
yading@10: 
yading@10:     return ret;
yading@10: }
yading@10: 
yading@10: static int mxpeg_check_dimensions(MXpegDecodeContext *s, MJpegDecodeContext *jpg,
yading@10:                                   AVFrame *reference_ptr)
yading@10: {
yading@10:     if ((jpg->width + 0x0F)>>4 != s->mb_width ||
yading@10:         (jpg->height + 0x0F)>>4 != s->mb_height) {
yading@10:         av_log(jpg->avctx, AV_LOG_ERROR,
yading@10:                "Picture dimensions stored in SOF and MXM mismatch\n");
yading@10:         return AVERROR(EINVAL);
yading@10:     }
yading@10: 
yading@10:     if (reference_ptr->data[0]) {
yading@10:         int i;
yading@10:         for (i = 0; i < MAX_COMPONENTS; ++i) {
yading@10:             if ( (!reference_ptr->data[i] ^ !jpg->picture_ptr->data[i]) ||
yading@10:                  reference_ptr->linesize[i] != jpg->picture_ptr->linesize[i]) {
yading@10:                 av_log(jpg->avctx, AV_LOG_ERROR,
yading@10:                        "Dimensions of current and reference picture mismatch\n");
yading@10:                 return AVERROR(EINVAL);
yading@10:             }
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: static int mxpeg_decode_frame(AVCodecContext *avctx,
yading@10:                           void *data, int *got_frame,
yading@10:                           AVPacket *avpkt)
yading@10: {
yading@10:     const uint8_t *buf = avpkt->data;
yading@10:     int buf_size = avpkt->size;
yading@10:     MXpegDecodeContext *s = avctx->priv_data;
yading@10:     MJpegDecodeContext *jpg = &s->jpg;
yading@10:     const uint8_t *buf_end, *buf_ptr;
yading@10:     const uint8_t *unescaped_buf_ptr;
yading@10:     int unescaped_buf_size;
yading@10:     int start_code;
yading@10:     int ret;
yading@10: 
yading@10:     buf_ptr = buf;
yading@10:     buf_end = buf + buf_size;
yading@10:     jpg->got_picture = 0;
yading@10:     s->got_mxm_bitmask = 0;
yading@10:     while (buf_ptr < buf_end) {
yading@10:         start_code = ff_mjpeg_find_marker(jpg, &buf_ptr, buf_end,
yading@10:                                           &unescaped_buf_ptr, &unescaped_buf_size);
yading@10:         if (start_code < 0)
yading@10:             goto the_end;
yading@10:         {
yading@10:             init_get_bits(&jpg->gb, unescaped_buf_ptr, unescaped_buf_size*8);
yading@10: 
yading@10:             if (start_code >= APP0 && start_code <= APP15) {
yading@10:                 mxpeg_decode_app(s, unescaped_buf_ptr, unescaped_buf_size);
yading@10:             }
yading@10: 
yading@10:             switch (start_code) {
yading@10:             case SOI:
yading@10:                 if (jpg->got_picture) //emulating EOI
yading@10:                     goto the_end;
yading@10:                 break;
yading@10:             case EOI:
yading@10:                 goto the_end;
yading@10:             case DQT:
yading@10:                 ret = ff_mjpeg_decode_dqt(jpg);
yading@10:                 if (ret < 0) {
yading@10:                     av_log(avctx, AV_LOG_ERROR,
yading@10:                            "quantization table decode error\n");
yading@10:                     return ret;
yading@10:                 }
yading@10:                 break;
yading@10:             case DHT:
yading@10:                 ret = ff_mjpeg_decode_dht(jpg);
yading@10:                 if (ret < 0) {
yading@10:                     av_log(avctx, AV_LOG_ERROR,
yading@10:                            "huffman table decode error\n");
yading@10:                     return ret;
yading@10:                 }
yading@10:                 break;
yading@10:             case COM:
yading@10:                 ret = mxpeg_decode_com(s, unescaped_buf_ptr,
yading@10:                                        unescaped_buf_size);
yading@10:                 if (ret < 0)
yading@10:                     return ret;
yading@10:                 break;
yading@10:             case SOF0:
yading@10:                 s->got_sof_data = 0;
yading@10:                 ret = ff_mjpeg_decode_sof(jpg);
yading@10:                 if (ret < 0) {
yading@10:                     av_log(avctx, AV_LOG_ERROR,
yading@10:                            "SOF data decode error\n");
yading@10:                     return ret;
yading@10:                 }
yading@10:                 if (jpg->interlaced) {
yading@10:                     av_log(avctx, AV_LOG_ERROR,
yading@10:                            "Interlaced mode not supported in MxPEG\n");
yading@10:                     return AVERROR(EINVAL);
yading@10:                 }
yading@10:                 s->got_sof_data = 1;
yading@10:                 break;
yading@10:             case SOS:
yading@10:                 if (!s->got_sof_data) {
yading@10:                     av_log(avctx, AV_LOG_WARNING,
yading@10:                            "Can not process SOS without SOF data, skipping\n");
yading@10:                     break;
yading@10:                 }
yading@10:                 if (!jpg->got_picture) {
yading@10:                     if (jpg->first_picture) {
yading@10:                         av_log(avctx, AV_LOG_WARNING,
yading@10:                                "First picture has no SOF, skipping\n");
yading@10:                         break;
yading@10:                     }
yading@10:                     if (!s->got_mxm_bitmask){
yading@10:                         av_log(avctx, AV_LOG_WARNING,
yading@10:                                "Non-key frame has no MXM, skipping\n");
yading@10:                         break;
yading@10:                     }
yading@10:                     /* use stored SOF data to allocate current picture */
yading@10:                     av_frame_unref(jpg->picture_ptr);
yading@10:                     if ((ret = ff_get_buffer(avctx, jpg->picture_ptr,
yading@10:                                              AV_GET_BUFFER_FLAG_REF)) < 0)
yading@10:                         return ret;
yading@10:                     jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_P;
yading@10:                     jpg->picture_ptr->key_frame = 0;
yading@10:                     jpg->got_picture = 1;
yading@10:                 } else {
yading@10:                     jpg->picture_ptr->pict_type = AV_PICTURE_TYPE_I;
yading@10:                     jpg->picture_ptr->key_frame = 1;
yading@10:                 }
yading@10: 
yading@10:                 if (s->got_mxm_bitmask) {
yading@10:                     AVFrame *reference_ptr = &s->picture[s->picture_index ^ 1];
yading@10:                     if (mxpeg_check_dimensions(s, jpg, reference_ptr) < 0)
yading@10:                         break;
yading@10: 
yading@10:                     /* allocate dummy reference picture if needed */
yading@10:                     if (!reference_ptr->data[0] &&
yading@10:                         (ret = ff_get_buffer(avctx, reference_ptr,
yading@10:                                              AV_GET_BUFFER_FLAG_REF)) < 0)
yading@10:                         return ret;
yading@10: 
yading@10:                     ret = ff_mjpeg_decode_sos(jpg, s->mxm_bitmask, reference_ptr);
yading@10:                     if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
yading@10:                         return ret;
yading@10:                 } else {
yading@10:                     ret = ff_mjpeg_decode_sos(jpg, NULL, NULL);
yading@10:                     if (ret < 0 && (avctx->err_recognition & AV_EF_EXPLODE))
yading@10:                         return ret;
yading@10:                 }
yading@10: 
yading@10:                 break;
yading@10:             }
yading@10: 
yading@10:             buf_ptr += (get_bits_count(&jpg->gb)+7) >> 3;
yading@10:         }
yading@10: 
yading@10:     }
yading@10: 
yading@10: the_end:
yading@10:     if (jpg->got_picture) {
yading@10:         int ret = av_frame_ref(data, jpg->picture_ptr);
yading@10:         if (ret < 0)
yading@10:             return ret;
yading@10:         *got_frame = 1;
yading@10: 
yading@10:         s->picture_index ^= 1;
yading@10:         jpg->picture_ptr = &s->picture[s->picture_index];
yading@10: 
yading@10:         if (!s->has_complete_frame) {
yading@10:             if (!s->got_mxm_bitmask)
yading@10:                 s->has_complete_frame = 1;
yading@10:             else
yading@10:                 *got_frame = 0;
yading@10:         }
yading@10:     }
yading@10: 
yading@10:     return buf_ptr - buf;
yading@10: }
yading@10: 
yading@10: static av_cold int mxpeg_decode_end(AVCodecContext *avctx)
yading@10: {
yading@10:     MXpegDecodeContext *s = avctx->priv_data;
yading@10:     MJpegDecodeContext *jpg = &s->jpg;
yading@10:     int i;
yading@10: 
yading@10:     jpg->picture_ptr = NULL;
yading@10:     ff_mjpeg_decode_end(avctx);
yading@10: 
yading@10:     for (i = 0; i < 2; ++i)
yading@10:         av_frame_unref(&s->picture[i]);
yading@10: 
yading@10:     av_freep(&s->mxm_bitmask);
yading@10:     av_freep(&s->completion_bitmask);
yading@10: 
yading@10:     return 0;
yading@10: }
yading@10: 
yading@10: AVCodec ff_mxpeg_decoder = {
yading@10:     .name           = "mxpeg",
yading@10:     .long_name      = NULL_IF_CONFIG_SMALL("Mobotix MxPEG video"),
yading@10:     .type           = AVMEDIA_TYPE_VIDEO,
yading@10:     .id             = AV_CODEC_ID_MXPEG,
yading@10:     .priv_data_size = sizeof(MXpegDecodeContext),
yading@10:     .init           = mxpeg_decode_init,
yading@10:     .close          = mxpeg_decode_end,
yading@10:     .decode         = mxpeg_decode_frame,
yading@10:     .capabilities   = CODEC_CAP_DR1,
yading@10:     .max_lowres     = 3,
yading@10: };