ARMovie/RPL demuxer

Patch by Eli Friedman (eli friedman gmail com)

Originally committed as revision 12649 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavformat/Makefile

@@ -145,6 +145,7 @@ OBJS-$(CONFIG_RM_DEMUXER)                += rmdec.o
 OBJS-$(CONFIG_RM_MUXER)                  += rmenc.o
 OBJS-$(CONFIG_ROQ_DEMUXER)               += idroq.o
 OBJS-$(CONFIG_ROQ_MUXER)                 += raw.o
+OBJS-$(CONFIG_RPL_DEMUXER)               += rpl.o
 OBJS-$(CONFIG_RTP_MUXER)                 += rtp.o         \
                                             rtpenc.o      \
                                             rtp_mpv.o     \

libavformat/allformats.c

@@ -140,6 +140,7 @@ void av_register_all(void)
     REGISTER_DEMUXER  (RL2, rl2);
     REGISTER_MUXDEMUX (RM, rm);
     REGISTER_MUXDEMUX (ROQ, roq);
+    REGISTER_DEMUXER  (RPL, rpl);
     REGISTER_MUXER    (RTP, rtp);
     REGISTER_DEMUXER  (RTSP, rtsp);
     REGISTER_DEMUXER  (SDP, sdp);

libavformat/rpl.c

@@ -0,0 +1,356 @@
+/*
+ * ARMovie/RPL demuxer
+ * Copyright (c) 2007 Christian Ohm, 2008 Eli Friedman
+ *
+ * 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 "avformat.h"
+#include "avstring.h"
+#include <stdlib.h>
+
+#define RPL_SIGNATURE "ARMovie\x0A"
+#define RPL_SIGNATURE_SIZE 8
+
+/** 256 is arbitrary, but should be big enough for any reasonable file. */
+#define RPL_LINE_LENGTH 256
+
+static int rpl_probe(AVProbeData *p)
+{
+    if (memcmp(p->buf, RPL_SIGNATURE, RPL_SIGNATURE_SIZE))
+        return 0;
+
+    return AVPROBE_SCORE_MAX;
+}
+
+typedef struct RPLContext {
+    // RPL header data
+    int32_t frames_per_chunk;
+
+    // Stream position data
+    uint32_t chunk_number;
+    uint32_t chunk_part;
+    uint32_t frame_in_part;
+} RPLContext;
+
+static int read_line(ByteIOContext * pb, char* line, int bufsize)
+{
+    int i;
+    for (i = 0; i < bufsize - 1; i++) {
+        int b = get_byte(pb);
+        if (b == 0)
+            break;
+        if (b == '\n') {
+            line[i] = '\0';
+            return 0;
+        }
+        line[i] = b;
+    }
+    line[i] = '\0';
+    return -1;
+}
+
+static int32_t read_int(const char* line, const char** endptr, int* error)
+{
+    unsigned long result = 0;
+    for (; *line>='0' && *line<='9'; line++) {
+        if (result > (0x7FFFFFFF - 9) / 10)
+            *error = -1;
+        result = 10 * result + *line - '0';
+    }
+    *endptr = line;
+    return result;
+}
+
+static int32_t read_line_and_int(ByteIOContext * pb, int* error)
+{
+    char line[RPL_LINE_LENGTH];
+    const char *endptr;
+    *error |= read_line(pb, line, sizeof(line));
+    return read_int(line, &endptr, error);
+}
+
+/** Parsing for fps, which can be a fraction. Unfortunately,
+  * the spec for the header leaves out a lot of details,
+  * so this is mostly guessing.
+  */
+static AVRational read_fps(const char* line, int* error)
+{
+    int64_t num, den = 1;
+    AVRational result;
+    num = read_int(line, &line, error);
+    if (*line == '.')
+        line++;
+    for (; *line>='0' && *line<='9'; line++) {
+        // Truncate any numerator too large to fit into an int64_t
+        if (num > (INT64_MAX - 9) / 10 || den > INT64_MAX / 10)
+            break;
+        num  = 10 * num + *line - '0';
+        den *= 10;
+    }
+    if (!num)
+        *error = -1;
+    av_reduce(&result.num, &result.den, num, den, 0x7FFFFFFF);
+    return result;
+}
+
+static int rpl_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+    ByteIOContext *pb = s->pb;
+    RPLContext *rpl = s->priv_data;
+    AVStream *vst = NULL, *ast = NULL;
+    int total_audio_size;
+    int error = 0;
+
+    uint32_t i;
+
+    int32_t audio_format, chunk_catalog_offset, number_of_chunks;
+    AVRational fps;
+
+    char line[RPL_LINE_LENGTH];
+
+    // The header for RPL/ARMovie files is 21 lines of text
+    // containing the various header fields.  The fields are always
+    // in the same order, and other text besides the first
+    // number usually isn't important.
+    // (The spec says that there exists some significance
+    // for the text in a few cases; samples needed.)
+    error |= read_line(pb, line        , sizeof(line        ));  // ARMovie
+    error |= read_line(pb, s->title    , sizeof(s->title    ));  // movie name
+    error |= read_line(pb, s->copyright, sizeof(s->copyright));  // date/copyright
+    error |= read_line(pb, s->author   , sizeof(s->author   ));  // author and other
+
+    // video headers
+    vst = av_new_stream(s, 0);
+    if (!vst)
+        return AVERROR(ENOMEM);
+    vst->codec->codec_type      = CODEC_TYPE_VIDEO;
+    vst->codec->codec_tag       = read_line_and_int(pb, &error);  // video format
+    vst->codec->width           = read_line_and_int(pb, &error);  // video width
+    vst->codec->height          = read_line_and_int(pb, &error);  // video height
+    vst->codec->bits_per_sample = read_line_and_int(pb, &error);  // video bits per sample
+    error |= read_line(pb, line, sizeof(line));                   // video frames per second
+    fps = read_fps(line, &error);
+    av_set_pts_info(vst, 32, fps.den, fps.num);
+
+    // Figure out the video codec
+    switch (vst->codec->codec_tag) {
+#if 0
+        case 122:
+            vst->codec->codec_id = CODEC_ID_ESCAPE122;
+            break;
+#endif
+        case 124:
+            vst->codec->codec_id = CODEC_ID_ESCAPE124;
+            // The header is wrong here, at least sometimes
+            vst->codec->bits_per_sample = 16;
+            break;
+#if 0
+        case 130:
+            vst->codec->codec_id = CODEC_ID_ESCAPE130;
+            break;
+#endif
+        default:
+            av_log(s, AV_LOG_WARNING,
+                   "RPL video format %i not supported yet!\n",
+                   vst->codec->codec_tag);
+            vst->codec->codec_id = CODEC_ID_NONE;
+    }
+
+    // Audio headers
+
+    // ARMovie supports multiple audio tracks; I don't have any
+    // samples, though. This code will ignore additional tracks.
+    audio_format = read_line_and_int(pb, &error);  // audio format ID
+    if (audio_format) {
+        ast = av_new_stream(s, 0);
+        if (!ast)
+            return AVERROR(ENOMEM);
+        ast->codec->codec_type      = CODEC_TYPE_AUDIO;
+        ast->codec->codec_tag       = audio_format;
+        ast->codec->sample_rate     = read_line_and_int(pb, &error);  // audio bitrate
+        ast->codec->channels        = read_line_and_int(pb, &error);  // number of audio channels
+        ast->codec->bits_per_sample = read_line_and_int(pb, &error);  // audio bits per sample
+        // At least one sample uses 0 for ADPCM, which is really 4 bits
+        // per sample.
+        if (ast->codec->bits_per_sample == 0)
+            ast->codec->bits_per_sample = 4;
+
+        ast->codec->bit_rate = ast->codec->sample_rate *
+                               ast->codec->bits_per_sample *
+                               ast->codec->channels;
+
+        ast->codec->codec_id = CODEC_ID_NONE;
+        switch (audio_format) {
+            case 1:
+                if (ast->codec->bits_per_sample == 16) {
+                    // 16-bit audio is always signed
+                    ast->codec->codec_id = CODEC_ID_PCM_S16LE;
+                    break;
+                }
+                // There are some other formats listed as legal per the spec;
+                // samples needed.
+                break;
+            case 101:
+                if (ast->codec->bits_per_sample == 8) {
+                    // The samples with this kind of audio that I have
+                    // are all unsigned.
+                    ast->codec->codec_id = CODEC_ID_PCM_U8;
+                    break;
+                } else if (ast->codec->bits_per_sample == 4) {
+                    ast->codec->codec_id = CODEC_ID_ADPCM_IMA_EA_SEAD;
+                    break;
+                }
+                break;
+        }
+        if (ast->codec->codec_id == CODEC_ID_NONE) {
+            av_log(s, AV_LOG_WARNING,
+                   "RPL audio format %i not supported yet!\n",
+                   audio_format);
+        }
+        av_set_pts_info(ast, 32, 1, ast->codec->bit_rate);
+    } else {
+        for (i = 0; i < 3; i++)
+            error |= read_line(pb, line, sizeof(line));
+    }
+
+    rpl->frames_per_chunk = read_line_and_int(pb, &error);  // video frames per chunk
+    if (rpl->frames_per_chunk > 1 && vst->codec->codec_tag != 124)
+        av_log(s, AV_LOG_WARNING,
+               "Don't know how to split frames for video format %i. "
+               "Video stream will be broken!\n", vst->codec->codec_tag);
+
+    number_of_chunks = read_line_and_int(pb, &error);  // number of chunks in the file
+    // The number in the header is actually the index of the last chunk.
+    number_of_chunks++;
+
+    error |= read_line(pb, line, sizeof(line));  // "even" chunk size in bytes
+    error |= read_line(pb, line, sizeof(line));  // "odd" chunk size in bytes
+    chunk_catalog_offset =                       // offset of the "chunk catalog"
+        read_line_and_int(pb, &error);           //   (file index)
+    error |= read_line(pb, line, sizeof(line));  // offset to "helpful" sprite
+    error |= read_line(pb, line, sizeof(line));  // size of "helpful" sprite
+    error |= read_line(pb, line, sizeof(line));  // offset to key frame list
+
+    // Read the index
+    url_fseek(pb, chunk_catalog_offset, SEEK_SET);
+    total_audio_size = 0;
+    for (i = 0; i < number_of_chunks; i++) {
+        int64_t offset, video_size, audio_size;
+        error |= read_line(pb, line, sizeof(line));
+        if (3 != sscanf(line, "%"PRId64" , %"PRId64" ; %"PRId64,
+                        &offset, &video_size, &audio_size))
+            error = -1;
+        av_add_index_entry(vst, offset, i * rpl->frames_per_chunk,
+                           video_size, rpl->frames_per_chunk, 0);
+        if (ast)
+            av_add_index_entry(ast, offset + video_size, total_audio_size,
+                               audio_size, audio_size * 8, 0);
+        total_audio_size += audio_size * 8;
+    }
+
+    if (error) return AVERROR(EIO);
+
+    return 0;
+}
+
+static int rpl_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    RPLContext *rpl = s->priv_data;
+    ByteIOContext *pb = s->pb;
+    AVStream* stream;
+    AVIndexEntry* index_entry;
+    uint32_t ret;
+
+    if (rpl->chunk_part == s->nb_streams) {
+        rpl->chunk_number++;
+        rpl->chunk_part = 0;
+    }
+
+    stream = s->streams[rpl->chunk_part];
+
+    if (rpl->chunk_number >= stream->nb_index_entries)
+        return -1;
+
+    index_entry = &stream->index_entries[rpl->chunk_number];
+
+    if (rpl->frame_in_part == 0)
+        if (url_fseek(pb, index_entry->pos, SEEK_SET) < 0)
+            return AVERROR(EIO);
+
+    if (stream->codec->codec_type == CODEC_TYPE_VIDEO &&
+        stream->codec->codec_tag == 124) {
+        // We have to split Escape 124 frames because there are
+        // multiple frames per chunk in Escape 124 samples.
+        uint32_t frame_size, frame_flags;
+
+        frame_flags = get_le32(pb);
+        frame_size = get_le32(pb);
+        if (url_fseek(pb, -8, SEEK_CUR) < 0)
+            return AVERROR(EIO);
+
+        ret = av_get_packet(pb, pkt, frame_size);
+        if (ret != frame_size) {
+            av_free_packet(pkt);
+            return AVERROR(EIO);
+        }
+        pkt->duration = 1;
+        pkt->pts = index_entry->timestamp + rpl->frame_in_part;
+        pkt->stream_index = rpl->chunk_part;
+
+        rpl->frame_in_part++;
+        if (rpl->frame_in_part == rpl->frames_per_chunk) {
+            rpl->frame_in_part = 0;
+            rpl->chunk_part++;
+        }
+    } else {
+        ret = av_get_packet(pb, pkt, index_entry->size);
+        if (ret != index_entry->size) {
+            av_free_packet(pkt);
+            return AVERROR(EIO);
+        }
+
+        if (stream->codec->codec_type == CODEC_TYPE_VIDEO) {
+            // frames_per_chunk should always be one here; the header
+            // parsing will warn if it isn't.
+            pkt->duration = rpl->frames_per_chunk;
+        } else {
+            // All the audio codecs supported in this container
+            // (at least so far) are constant-bitrate.
+            pkt->duration = ret * 8;
+        }
+        pkt->pts = index_entry->timestamp;
+        pkt->stream_index = rpl->chunk_part;
+        rpl->chunk_part++;
+    }
+
+    // None of the Escape formats have keyframes, and the ADPCM
+    // format used doesn't have keyframes.
+    if (rpl->chunk_number == 0 && rpl->frame_in_part == 0)
+        pkt->flags |= PKT_FLAG_KEY;
+
+    return ret;
+}
+
+AVInputFormat rpl_demuxer = {
+    "rpl",
+    "RPL/ARMovie format",
+    sizeof(RPLContext),
+    rpl_probe,
+    rpl_read_header,
+    rpl_read_packet,
+};