X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=libavformat%2Fa64.c;h=0e5576b651555ff75400d3cc5e61db0a93a0351c;hb=29a290439ba28fde00b2a27d5afef863c63abb37;hp=32ed00b0632929937adb34e1b2aad12d8a76e6eb;hpb=bb07ab7cf22e7bf0717264f9e7b15dfb6d67e391;p=ffmpeg diff --git a/libavformat/a64.c b/libavformat/a64.c index 32ed00b0632..0e5576b6515 100644 --- a/libavformat/a64.c +++ b/libavformat/a64.c @@ -2,20 +2,20 @@ * a64 muxer * Copyright (c) 2009 Tobias Bindhammer * - * This file is part of FFmpeg. + * This file is part of Libav. * - * FFmpeg is free software; you can redistribute it and/or + * Libav 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, + * Libav 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 + * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -24,9 +24,16 @@ #include "libavcodec/bytestream.h" #include "avformat.h" +typedef struct A64MuxerContext { + int interleaved; + AVPacket prev_pkt; + int prev_frame_count; +} A64MuxerContext; + static int a64_write_header(struct AVFormatContext *s) { - AVCodecContext *avctx=s->streams[0]->codec; + AVCodecContext *avctx = s->streams[0]->codec; + A64MuxerContext *c = s->priv_data; uint8_t header[5] = { 0x00, //load 0x40, //address @@ -34,33 +41,130 @@ static int a64_write_header(struct AVFormatContext *s) 0x00, //charset_lifetime (multi only) 0x00 //fps in 50/fps; }; + c->interleaved = 0; switch (avctx->codec->id) { case CODEC_ID_A64_MULTI: header[2] = 0x00; - header[3] = 4; + header[3] = AV_RB32(avctx->extradata+0); header[4] = 2; break; case CODEC_ID_A64_MULTI5: header[2] = 0x01; - header[3] = 4; + header[3] = AV_RB32(avctx->extradata+0); header[4] = 3; break; default: return AVERROR(EINVAL); break; } - put_buffer(s->pb, header, 2); + avio_write(s->pb, header, 2); + c->prev_pkt.size = 0; + c->prev_frame_count = 0; return 0; } static int a64_write_packet(struct AVFormatContext *s, AVPacket *pkt) { - put_buffer(s->pb, pkt->data, pkt->size); - put_flush_packet(s->pb); + AVCodecContext *avctx = s->streams[0]->codec; + A64MuxerContext *c = s->priv_data; + int i, j; + int ch_chunksize; + int lifetime; + int frame_count; + int charset_size; + int frame_size; + int num_frames; + + /* fetch values from extradata */ + switch (avctx->codec->id) { + case CODEC_ID_A64_MULTI: + case CODEC_ID_A64_MULTI5: + if(c->interleaved) { + /* Write interleaved, means we insert chunks of the future charset before each current frame. + * Reason: if we load 1 charset + corresponding frames in one block on c64, we need to store + * them first and then display frame by frame to keep in sync. Thus we would read and write + * the data for colram from/to ram first and waste too much time. If we interleave and send the + * charset beforehand, we assemble a new charset chunk by chunk, write current screen data to + * screen-ram to be displayed and decode the colram directly to colram-location $d800 during + * the overscan, while reading directly from source. + * This is the only way so far, to achieve 25fps on c64 */ + if(avctx->extradata) { + /* fetch values from extradata */ + lifetime = AV_RB32(avctx->extradata + 0); + frame_count = AV_RB32(avctx->extradata + 4); + charset_size = AV_RB32(avctx->extradata + 8); + frame_size = AV_RB32(avctx->extradata + 12); + + /* TODO: sanity checks? */ + } else { + av_log(avctx, AV_LOG_ERROR, "extradata not set\n"); + return AVERROR(EINVAL); + } + + ch_chunksize=charset_size/lifetime; + /* TODO: check if charset/size is % lifetime, but maybe check in codec */ + + if(pkt->data) num_frames = lifetime; + else num_frames = c->prev_frame_count; + + for(i = 0; i < num_frames; i++) { + if(pkt->data) { + /* if available, put newest charset chunk into buffer */ + avio_write(s->pb, pkt->data + ch_chunksize * i, ch_chunksize); + } else { + /* a bit ugly, but is there an alternative to put many zeros? */ + for(j = 0; j < ch_chunksize; j++) avio_w8(s->pb, 0); + } + + if(c->prev_pkt.data) { + /* put frame (screen + colram) from last packet into buffer */ + avio_write(s->pb, c->prev_pkt.data + charset_size + frame_size * i, frame_size); + } else { + /* a bit ugly, but is there an alternative to put many zeros? */ + for(j = 0; j < frame_size; j++) avio_w8(s->pb, 0); + } + } + + /* backup current packet for next turn */ + if(pkt->data) { + /* no backup packet yet? create one! */ + if(!c->prev_pkt.data) av_new_packet(&c->prev_pkt, pkt->size); + /* we have a packet and data is big enough, reuse it */ + if(c->prev_pkt.data && c->prev_pkt.size >= pkt->size) { + memcpy(c->prev_pkt.data, pkt->data, pkt->size); + c->prev_pkt.size = pkt->size; + } else { + av_log(avctx, AV_LOG_ERROR, "Too less memory for prev_pkt.\n"); + return AVERROR(ENOMEM); + } + } + + c->prev_frame_count = frame_count; + break; + } + default: + /* Write things as is. Nice for self-contained frames from non-multicolor modes or if played + * directly from ram and not from a streaming device (rrnet/mmc) */ + if(pkt) avio_write(s->pb, pkt->data, pkt->size); + break; + } + + avio_flush(s->pb); + return 0; +} + +static int a64_write_trailer(struct AVFormatContext *s) +{ + A64MuxerContext *c = s->priv_data; + AVPacket pkt = {0}; + /* need to flush last packet? */ + if(c->interleaved) a64_write_packet(s, &pkt); + /* discard backed up packet */ + if(c->prev_pkt.data) av_destruct_packet(&c->prev_pkt); return 0; } -AVOutputFormat a64_muxer = { +AVOutputFormat ff_a64_muxer = { .name = "a64", .long_name = NULL_IF_CONFIG_SMALL("a64 - video for Commodore 64"), .mime_type = NULL, @@ -69,4 +173,5 @@ AVOutputFormat a64_muxer = { .video_codec = CODEC_ID_A64_MULTI, a64_write_header, a64_write_packet, + a64_write_trailer };