/* * V4L2 mem2mem decoders * * Copyright (C) 2017 Alexis Ballier * Copyright (C) 2017 Jorge Ramirez * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include #include "libavutil/pixfmt.h" #include "libavutil/pixdesc.h" #include "libavutil/opt.h" #include "libavcodec/avcodec.h" #include "libavcodec/decode.h" #include "v4l2_context.h" #include "v4l2_m2m.h" #include "v4l2_fmt.h" static int v4l2_try_start(AVCodecContext *avctx) { V4L2m2mContext *s = ((V4L2m2mPriv*)avctx->priv_data)->context; V4L2Context *const capture = &s->capture; V4L2Context *const output = &s->output; struct v4l2_selection selection; int ret; /* 1. start the output process */ if (!output->streamon) { ret = ff_v4l2_context_set_status(output, VIDIOC_STREAMON); if (ret < 0) { av_log(avctx, AV_LOG_DEBUG, "VIDIOC_STREAMON on output context\n"); return ret; } } if (capture->streamon) return 0; /* 2. get the capture format */ capture->format.type = capture->type; ret = ioctl(s->fd, VIDIOC_G_FMT, &capture->format); if (ret) { av_log(avctx, AV_LOG_WARNING, "VIDIOC_G_FMT ioctl\n"); return ret; } /* 2.1 update the AVCodecContext */ avctx->pix_fmt = ff_v4l2_format_v4l2_to_avfmt(capture->format.fmt.pix_mp.pixelformat, AV_CODEC_ID_RAWVIDEO); capture->av_pix_fmt = avctx->pix_fmt; /* 3. set the crop parameters */ selection.type = V4L2_BUF_TYPE_VIDEO_CAPTURE; selection.r.height = avctx->coded_height; selection.r.width = avctx->coded_width; ret = ioctl(s->fd, VIDIOC_S_SELECTION, &selection); if (!ret) { ret = ioctl(s->fd, VIDIOC_G_SELECTION, &selection); if (ret) { av_log(avctx, AV_LOG_WARNING, "VIDIOC_G_SELECTION ioctl\n"); } else { av_log(avctx, AV_LOG_DEBUG, "crop output %dx%d\n", selection.r.width, selection.r.height); /* update the size of the resulting frame */ capture->height = selection.r.height; capture->width = selection.r.width; } } /* 4. init the capture context now that we have the capture format */ if (!capture->buffers) { ret = ff_v4l2_context_init(capture); if (ret) { av_log(avctx, AV_LOG_ERROR, "can't request capture buffers\n"); return AVERROR(ENOMEM); } } /* 5. start the capture process */ ret = ff_v4l2_context_set_status(capture, VIDIOC_STREAMON); if (ret) { av_log(avctx, AV_LOG_DEBUG, "VIDIOC_STREAMON, on capture context\n"); return ret; } return 0; } static int v4l2_prepare_decoder(V4L2m2mContext *s) { struct v4l2_event_subscription sub; V4L2Context *output = &s->output; int ret; /** * requirements */ memset(&sub, 0, sizeof(sub)); sub.type = V4L2_EVENT_SOURCE_CHANGE; ret = ioctl(s->fd, VIDIOC_SUBSCRIBE_EVENT, &sub); if ( ret < 0) { if (output->height == 0 || output->width == 0) { av_log(s->avctx, AV_LOG_ERROR, "the v4l2 driver does not support VIDIOC_SUBSCRIBE_EVENT\n" "you must provide codec_height and codec_width on input\n"); return ret; } } return 0; } static int v4l2_receive_frame(AVCodecContext *avctx, AVFrame *frame) { V4L2m2mContext *s = ((V4L2m2mPriv*)avctx->priv_data)->context; V4L2Context *const capture = &s->capture; V4L2Context *const output = &s->output; AVPacket avpkt = {0}; int ret; if (s->buf_pkt.size) { avpkt = s->buf_pkt; memset(&s->buf_pkt, 0, sizeof(AVPacket)); } else { ret = ff_decode_get_packet(avctx, &avpkt); if (ret < 0 && ret != AVERROR_EOF) return ret; } if (s->draining) goto dequeue; ret = ff_v4l2_context_enqueue_packet(output, &avpkt); if (ret < 0) { if (ret != AVERROR(EAGAIN)) return ret; s->buf_pkt = avpkt; /* no input buffers available, continue dequeing */ } if (avpkt.size) { ret = v4l2_try_start(avctx); if (ret) { av_packet_unref(&avpkt); /* cant recover */ if (ret == AVERROR(ENOMEM)) return ret; return 0; } } dequeue: if (!s->buf_pkt.size) av_packet_unref(&avpkt); return ff_v4l2_context_dequeue_frame(capture, frame, -1); } static av_cold int v4l2_decode_init(AVCodecContext *avctx) { V4L2Context *capture, *output; V4L2m2mContext *s; V4L2m2mPriv *priv = avctx->priv_data; int ret; ret = ff_v4l2_m2m_create_context(priv, &s); if (ret < 0) return ret; capture = &s->capture; output = &s->output; /* if these dimensions are invalid (ie, 0 or too small) an event will be raised * by the v4l2 driver; this event will trigger a full pipeline reconfig and * the proper values will be retrieved from the kernel driver. */ output->height = capture->height = avctx->coded_height; output->width = capture->width = avctx->coded_width; output->av_codec_id = avctx->codec_id; output->av_pix_fmt = AV_PIX_FMT_NONE; capture->av_codec_id = AV_CODEC_ID_RAWVIDEO; capture->av_pix_fmt = avctx->pix_fmt; ret = ff_v4l2_m2m_codec_init(priv); if (ret) { av_log(avctx, AV_LOG_ERROR, "can't configure decoder\n"); s->self_ref = NULL; av_buffer_unref(&priv->context_ref); return ret; } s->avctx = avctx; return v4l2_prepare_decoder(s); } static av_cold int v4l2_decode_close(AVCodecContext *avctx) { V4L2m2mPriv *priv = avctx->priv_data; V4L2m2mContext* s = priv->context; av_packet_unref(&s->buf_pkt); return ff_v4l2_m2m_codec_end(priv); } #define OFFSET(x) offsetof(V4L2m2mPriv, x) #define FLAGS AV_OPT_FLAG_VIDEO_PARAM | AV_OPT_FLAG_DECODING_PARAM static const AVOption options[] = { V4L_M2M_DEFAULT_OPTS, { "num_capture_buffers", "Number of buffers in the capture context", OFFSET(num_capture_buffers), AV_OPT_TYPE_INT, {.i64 = 20}, 20, INT_MAX, FLAGS }, { NULL}, }; #define M2MDEC_CLASS(NAME) \ static const AVClass v4l2_m2m_ ## NAME ## _dec_class = { \ .class_name = #NAME "_v4l2m2m_decoder", \ .item_name = av_default_item_name, \ .option = options, \ .version = LIBAVUTIL_VERSION_INT, \ }; #define M2MDEC(NAME, LONGNAME, CODEC, bsf_name) \ M2MDEC_CLASS(NAME) \ AVCodec ff_ ## NAME ## _v4l2m2m_decoder = { \ .name = #NAME "_v4l2m2m" , \ .long_name = NULL_IF_CONFIG_SMALL("V4L2 mem2mem " LONGNAME " decoder wrapper"), \ .type = AVMEDIA_TYPE_VIDEO, \ .id = CODEC , \ .priv_data_size = sizeof(V4L2m2mPriv), \ .priv_class = &v4l2_m2m_ ## NAME ## _dec_class, \ .init = v4l2_decode_init, \ .receive_frame = v4l2_receive_frame, \ .close = v4l2_decode_close, \ .bsfs = bsf_name, \ .capabilities = AV_CODEC_CAP_HARDWARE | AV_CODEC_CAP_DELAY | AV_CODEC_CAP_AVOID_PROBING, \ .caps_internal = FF_CODEC_CAP_SETS_PKT_DTS, \ .wrapper_name = "v4l2m2m", \ }; M2MDEC(h264, "H.264", AV_CODEC_ID_H264, "h264_mp4toannexb"); M2MDEC(hevc, "HEVC", AV_CODEC_ID_HEVC, "hevc_mp4toannexb"); M2MDEC(mpeg1, "MPEG1", AV_CODEC_ID_MPEG1VIDEO, NULL); M2MDEC(mpeg2, "MPEG2", AV_CODEC_ID_MPEG2VIDEO, NULL); M2MDEC(mpeg4, "MPEG4", AV_CODEC_ID_MPEG4, NULL); M2MDEC(h263, "H.263", AV_CODEC_ID_H263, NULL); M2MDEC(vc1 , "VC1", AV_CODEC_ID_VC1, NULL); M2MDEC(vp8, "VP8", AV_CODEC_ID_VP8, NULL); M2MDEC(vp9, "VP9", AV_CODEC_ID_VP9, NULL);